Here's what I do and I know some people will disagree with me but, oh well...it's what works for me!
At around 2 and half to 3 weeks old, I take the kits and put them in their own cage. If I have multiple litters I keep them all together if they're around the same age.
I give them bowls full of oats mixed in with some pellets, lots of hay, and 2 shallow bowls of water. Sometimes, if I know they're drinking from a water bottle, i'll put one in there along with the bowls.
They stay in that cage all day and I put them back in with their dams at night.
The next morning they all go back into their own cage.
I do that until they're about 4 weeks old, then they start spending nights in their grow-out cage (without mom) and at some point during the day i'll put them in their dam's cages for milk for about 5 minutes or until they've all had enough milk.
I completely wean all my kits at 5 weeks...sometimes 6 weeks if I have a 'weakly' kit that I feel needs more time.
And I keep them all on oats mixed with pellets until they're about 8 weeks old, then they get just pellets.
Hope this helps!