Wees when engrossed!

[LisaV77]

Our 3 year old DS has been doing really well with potty training so far, but it's still down to us to get him to go to the potty or toilet. He won't ask to go, and sometimes when he's totally engrossed in something, he'll just wee and sit in wet pants.
Trying really hard not to sound disappointed when he does it, but sometimes I don't succeed!
He will take himself to the potty sometimes, but mostly only when we remind him.
He starts pre school in September, so would love it if he could be properly dry by then (daytime....we'll work on the night time later!)

Any tips out there on how to get him to ask?

How long has it been?

You could try a sticker chart, so each time he does a wee he gets a sticker then a little reward when he has x amount of stickers.

It's not so much doing the wee. When we ask him, he'll go and generally speaking he'll be dry. Lots of praise etc.
It's when he's really engrossed in something, he'll just wee.