S.H.
Keep the potty chair (because it is portable) in any room he is in, close by.
Leave him naked on the bottom.
BUT, this will only work if he is ready for that.
We did that with our son.
So he got used to just having the potty around and to experiment and play around on it.
Then one day, when he was already 3... he started to go on it.
We let him.
Per HIS.... readiness.
Never pushing it.
It goes in stages.
Not all at one time.
It is a progression....
IF the child, is ready.
What your son is doing, is preliminary... he is warming up to the idea, but not there yet.
But sure, just let him go at his own pace.
Then it will be better.
Never force it.
If they want a diaper in the meantime, fine.
Let them.
Because... this is ALL a part of the process.
Then one day, they will do it in a toilet.
Its fine if he is pretending for now.
Let him.
But don't force or lecture him, or expect too much.... for right now.
AND: Remember that kids WILL have Accidents... EVEN if they are already potty trained.
It is just childhood.
ALL of my daughter's Teachers, from Preschool to Kindergarten to 1st Grade, ALL said, kids these ages have Accidents.
It is normal.
It happens.
You don't have to punish or pressure or force, for every little accident.
Their Biological system, is still developing.
Now, for Night Time dryness... KEEP in mind, that this does not occur, physiologically, until even 7 years old, and is NORMAL.
You cannot train for night time dryness.
It is a SEPARATE process, from day time pottying.
Just get: Waterproof bed pads, to put under your child.
Even at 7 years old, my daughter had night time accidents. Normal. NO biggie.
I just changed out the bed pad, put a new one under her, she changed jammies and back to bed.
No big deal.
My daughter was 5 and still in night time diapers, because she was still wet. Not dry during the night.
Normal.