I know what you are going through. I have a son who will be 2 at the end of this month. Last Sept. He had two cousins come to town and they were being potty trained. After they left, we started potty training our son. One night at my in-laws and it was all over for him. It is a huge challenge at our house now, and I gave up for a month.
Try using pullups, if he is ready, he will love being a big boy and wearing big boy pants, they have a velcro type side to make changing him easy too.
Read "potty" books to him, there is one that you push a button and it makes sounds like a toilet flushing and a child cheering, there is the Elmo doll that is for potty training, and alot of books out there for parents. Not all of them will be right for you, but you will find one that is right for you.
Be persistant. If your son drinks alot throughout the day, put him on the potty every 30 minutes (wearing pullups allows you to see if he has gone---they have little designs on them that disappear or get blurry when they go-let him run around the house in a tee-shirt and his pull-up), if he goes, let him wipe (with help at first), and then flush the potty (makes them feel special and helpful), and don't forget to teach him to wash his hands with toddler soap (huggies has one with a purple hippo on it). Give a reward-a special treat or sticker after he does go on the potty. Let him call Daddy (or grandma) and make it a big deal, he will feel like a big boy.
If after the first week he isn't getting it, or not going on the potty, you can change the wait time to 15 minutes, or wait a couple of weeks and try again. But don't wait too long to try again. Get into a routine of going and that will help too. Do your best if you go to a mall or store and he tells you he has to go, sometimes they are not the cleanest bathrooms and are often times really disgusting, those are the hardest places to use the potties especially if your little one won't use those potties because it isn't the same as his at home...I tell my son that it is ok, just this once to go in his pull-up then try to get home before he has to go again.
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