Random wondering.

[Badger]

How do you clean a plant they sleep on during the day?

I just move mine to a vine or leaf near to their current spot.

My frogs like to sit on each other alot, is this a normal thing, are they trying to mate, or just bored and keeping each other company?

A lot of White's have the tendency to do this. It's not them trying to mate, I'm sure of that. They have to hibernate before breeding. Probably just bored.

is it safe to let the complete clean go longer than 6 months?

I wouldn't go too far past 6, but I suppose as long as everything is in order.

Is it normal for them to be awake and active during the day?

Usually not, but as long as there is no weight loss/signs of sickness etc. He should be fine.