Hello and a warm welcome to GU,
Its generally recommended not to handle your Leo a lot, it will stress them out. However, its a good idea to get your Leo familiar with handling incase you need to administer medication etc.
The first thing you need to do is get him used to your hand and scent, so he realises you are not a threat, just do all daily maintenance in his tank each day, at night, place your hand in the enclosure for around fifteen minutes at a time, eventually your Leo should get used to your hand and investigate it, eventually after time, your Leo may climb on your hand and use it for warmth, let him lay on your hand for a couple of times and after two or so nights of him climbing on your hand, lift him up a few inches off the ground inside his cage , only lift him up a few inches in case he jumps or falls off your hand, then he won't hurt himself, slowly and surely, keep lifting him higher. Once he is at the height of his tank, lift him outside his tank over something soft, again in case he falls. Eventually you should be able to take him out and hold him in your lap without him being skittish!
Remember not to hold him for too long, or too often, it will stress them out. If you ever try to lift him out and he runs away just don't get him out that night and respect his decision.
If you ever need to lift him, approach him from the side, not above, slide as many fingers as you can underneath him and then lift him up, then put one hand in front of the hand you lifted him with so he can walk! Again be careful, they can move very fast when they want too!