When training your child to use the potty, teaching them to wash their hands straight after should also be part of the routine. Show them how to wash their hands properly with soap and to dry them after. If they have difficulty reaching the sink then put a nice little stool especially for them to use in the bathroom.
Check your child’s hands after they go to the toilet so that they know they have to wash their hands every time. If they have a tendency of not washing their hands then try a reward system where they get a sticker or a star when they wash their hands after using the bathroom (do not use sweets as a reward as you’ll have to give them a treat several times a day!).
Another way to encourage them to wash their hands is to get them their own special soap and hand towel. There are lots of cute, kids soaps and towels available so by getting them a special soap and towel they will find hand washing a little more fun. Eventually washing their hands after the potty and toilet will become automatic.