Should I encourage my leo to hibernate?

My reasoning for asking is for the sake of his weight not for breeding.

When I first got Vastervik, he was 80 grams and now he's 120 grams! I let him out of his cage to help give him exercise but still gaining weight that he really doesn't need.

Since the month are getting colder and he definitely has enough fat to last him, should I encourage Vastervik to hibernate?

If so, what are the steps I should take to be successful?

i have heard you slowly drop the temps until he sleeps.

hey the biggest gecko ever was about 200gs, i think you might have a giant. if he is and i didn't see you post that, sorry i am a skimmer when it comes to reading.

How much are you feeding him and how often?

Firstly, he's not a giant. As for feeding, I feed him four-five insects once every two days. I give Vastervik both superworms and crickets.

What is the ideal temperature I need to get to for hibernation? What are the signs I need to look for when he is in that state?