Rochelle from Home Sweet Homebodies shares a free pattern and tutorial for making a pair of potty training pants. They’re easy to pull on and pull off (important!). They’re made from soft knit fabric with a padded layer down the middle for absorbancy in case of an accident. The pattern is size 3T, but you could adjust it up or down as needed. Get the free pattern and tutorial.
[photo from Home Sweet Homebodies]