Get a rubber mattress protector pad. Have lots of patience. Don’t be afraid to delay night training if they aren’t ready. My understanding is that our bodies use hormone pathways to control bladder at night and those aren’t fully developed until as late as 5 years old.
Try not to make your kid anxious about it. They see you on the toilet, they are interested in going just like you eventually, it may not show at first. All three of my children potty trained at different times. Even our twins.
As long as you stick with it, they won’t be pissing themselves when they are 18, just remember that.
Now for advice on how to do it. We went bottomless the first couple days. Your child probably will prefer to be covered up and so letting them know that making it in the potty means they can get their big kid underwear is usually good motivation. After you feel comfortable putting them in underwear just be on them every 30 minutes to go potty. Give them the control to be able to say “I don’t have to go” once but not twice. Once they go awhile without an accident then you can move on to allowing them more skips.
It takes awhile to do. Don’t get discouraged
