Useful things to consider for each stage of development
What age is your baby?
Starting with a newborn (0-3 months)
Newborns tend to sleep a lot, feed and pee very frequently and overall are very sensitive to change. It's a great age to start toilet learning as they're very sensitive to feeling wet, don't move much (limiting mess), open to learning the norms of life, and their capacity for distraction is limited. Being vulnerable and very new to this world they are keen to communicate when they need something and you are likely to be observing their every move intensely.
Some newborns may be uncomfortable with the new sensations as their gut starts to work. They may cry because they feel the urge to go, are going, or have gone and feel wet. It is up to you to support them (via trial and error) to be comfortable so they know you are there for them, aware of whats going on for them and are looking for ways to help them.
Many people don't feel confident holding a very young baby in any other position than 'normal' so if you prefer to use a nappy to start with that's entirely OK. In fact, it is a great time just to do some observation and teach them the sound association once in a while.
Positions that work well for newborns (with head support)
Newborns want to be held close and need continual head support when you are holding them. The two best positions for newborns are the cradle hold and the back hold.
Your baby needs to feel safe and happy in whatever hold you put them in so they can relax into letting go. Ideally, have baby in a deep squat to help their body release (this puts gentle pressure on the bladder and straightens up the colon). Another benefit of the squat is that often very little wiping/cleaning up is needed.
Clothing tips for newborns
For naps you could lay them on a flat prefold and waterproof mat and just dress their top half (blanket to cover their lower half) so wake-up toileting is fast and easy (no pants or nappies getting in the way). If you prefer a nappy on then a singles, shirt, dress, sleep gown or legwarmers give quicker access than messing with pants or onesie snaps/zips. You can also simple tuck a prefold or muslin cloth into a nappy belt as a back up instead of a nappy with velcro or buttons.
Once settled in (3-6 months)
Many parents start toilet learning around this age, once they've settled in to having a new person in their home and once they are more comfortable with their babies level of head control. Confident caregivers give a more secure feeling during any in-arms toileting hold, which will help your baby to relax and be confident too.
Babies at this age may be signalling less if they feel their communication signals haven't been responded to previously but the fact they're now in more predictable routines may mean you have more success based on timing of their natural rhythms. Fortunately they are still not very mobile, which means any potential for mess is limited (relative to mobile babies).
It is common to notice the effects of a larger bladder and strengthened sphincter muscles at this age, meaning you may observe them holding a little longer. Maybe the nappy is dry more often upon waking and you have time to catch the pee (especially if you routinely offer after waking), or maybe you had them in the babycarrier slightly longer and find a dry nappy after and catch the pee as soon as you take them out.
Positions that work well for babies that can sit
Once a baby has started sitting by themselves you could incorporate an assisted sitting position, e.g. on an appropriately sized potty or a toilet seat reducer. It is important to support their middle so they don't accidentally lurch off and hurt themselves. They will start communicating their preferences for their favourite (most comfortable) positions and locations more often, so get confident with a few different ones so you can change it up when needed. Remember, you can still use the cradle hold and back hold anytime.
Clothing tips for rolling/crawling babies
Long or short sleeve shirts, or singlets, paired with a nappy and legwarmers works really well. If you have open-crotch leggings or chaps with a good waist-band they can be your nappy belt, keeping legs warm at the same time. Sleep-gowns with nappies are great for night-time instead of messing with onesies or sleeping-bags. A prefold or muslin cloth tucked into a nappy belt or chaps may come loose as they crawl if they're very active, so cloth nappies over chaps is a safer option.
When the mobility begins (6-9 months)
Now your baby is at an age where they are more mobile and more easily distracted it may be more of a challenge for your baby to stay focused and interested on the potty (long enough to relax and pee) so it comes down to the caregiver to make it as enjoyable and engaging as possible. A favourite toilet-time toy or looking into a mirror together (e.g. the one on the wall when toileting over a sink) can be useful, but if they aren't interested then just keep the offer short and try again later.
Your baby is going through many big developmental changes at this age so it is likely that toileting with you isn't a huge focus for them during this time so its entirely normal to take a few short breaks at this time. See our help section or FAQ's for more guidance around this.
As your baby is more aware of their surroundings at this age they may also have a strengthened desire for privacy keep that in mind when you offer. If you are in a strange place it might be worth reverting to the in-arm holds to reassure them or take them with you to various toilets when you're out an about so they see there are lots of places that you - their most trusted friend - goes.
Positions that work well for standing/walking babies
When your baby has started pulling themselves up on things and can stand comfortably for a few seconds you may find that for a short while they want to stand all the time, including to pee. If you aren't to worried about the chance of splash (e.g. by standing in the tub, sink or over a toilet or outside) it can be a fun way to mix it up; angling slightly forward can help minimise getting their feet wet, even for girls. Once the initial fascination has worn off most toileting will be back in a sitting squat or the back or cradle hold.
Clothing tips for standing/walking babies
Long or short sleeve shirts, or singlets, paired with a nappy and legwarmers still works well, but the benefit with a baby that can stand is that removing pull-ups/training pants becomes much easier than if they're sitting or held. If you're open to using no back-up for a while during the day you could try split pants; any squat opens the pants for a quick offer. Walking also makes wearing dresses much easier, which is the fastest-possible access and reduces the need to wear pants over the back-up.
Playful imitation stage (9-18 months)
If your baby has been wearing disposable nappies exclusively to this point they may have lost a bit of their bodily awareness or may have some trouble releasing their pee or poo in a set position (like sitting on a potty), and may even show strong attachment to their nappies (actually waiting for one to be put on before going). Respect this when guiding them, and take your time, and spend lots of time talking to them - and using sign language if you want - while you're observing or practicing. Also, swapping to cloth nappies would be very helpful now for them to experience that wetness feeling again more often.
At around one year of age babies are able to learn more complex sequences so if you offer consistently at routine times they will learn to anticipate these opportunities more than before. They are also much more mobile and clearer communicators, which can be helpful for others that may them take to the toilet too. The fact they also have bigger bladders and can go longer between pees is very useful if you've been practicing for a while, and you could consider moving to training pants to start incorporating that pull-down and pull-up action.
You can use your toddlers enthusiasm, curiosity and love of imitation to your advantage when leading their learning. They love being involved in the whole ritual and will want to help with wiping, putting paper in the toilet, flushing, washing hands afterwards. Dumping the contents of a potty in the toilet will also teach them the connection with the pee/poo and the toilet. Take advantage of this strong developmental drive to imitate you by applying an open door policy when you go to the toilet. Talk about the process step by step. Ask if someone else will do the same for them. Eventually, toddlers will enjoy taking their toys through the process, cueing them on their potty. You may like to get a potty-themed children's book to read with them. Learning through play works really well - keep the idea of pottying as fun as possible!
Older toddlers (18+ months)
The learning process can be the same for older children as described here for babies but other toilet training approaches - as long as they're implemented in a gentle and loving way - can also be of value. A merged method is available here.
As older children understand much more about the world it is very important to be careful not to coerce them, nor linger on any negative experiences involving toileting. They have big emotions for little people, with less ability to manage them than we think, and they need you to be on their side.
Keep talking to your child to help them learn about the process and make associations. Encourage them to poo near the toilet or potty, even if in the nappy, and keep inviting them to give it a try when they want to in a positive and relaxed tone. Let them be involved in the process by letting them pick where to use the potty or toilet, or which underwear to wear.
If your child is reluctant, try to look at it from their point of view. Consider how you would feel if you had to suddenly pee or poo in a different position and place to what you've been used to all of your life. Maybe you’ve experienced that feeling while on a camping trip?
It takes time to work out which muscles to use to release a pee in certain position. Respect their pace so they can remain comfortable because it can only happen if muscles get relaxed. Its normal and even healthy for the process to be very gradual.
If you are at a place where previous bad experiences have led to them forming a negative association with the toilet and are actually withholding poo or have constipation then that needs to be addressed first with help of your doctor.