They TOLERATE being handled, but I will bet money that they don't WANT to be handled.
If you gently handle them, handfeed sometimes, work in their enclosure, they'll learn that your hand isn't dangerous, nothing to worry about. Eventually they'll learn that 'the hand' is just another perch, one that sometimes comes complete with food - great combo deal, why not go along with it?
Even though we would love to think they like us, like being picked up and carried around, they just see us as a convenient tool towards some other goal. Unlike some reptiles or other pet species, Rhacs are fast to learn new tricks. The trick they do that we love the most is not running away from 'the hand'.
Leopard geckos do that eventually when they'r older and higher up the food chain, fat-tail geckos seem to lean it right out of the egg, maybe it's ESP for them. Even tokays can be tamed with patience. All we're really doing is teaching them that we aren't dangerous and if they sit on our hands or shoulders or heads and don't poop on us, we'll reward them with a treat.
I have some cresties that I handle, they like the trade-off ... sit on my hand for a few minutes and get a treat -- why not? Doesn't hurt and they probably like to see the silly grin on my face, makes them feel good to know they made another idiot happy

Some of mine just won't sit, they wont stay on anyone's hand, no way, no how. They don't care if they have to find their own food and think I look silly with that idiotic grin anyways, so let them be, thank you very much.
It all depends on the crestie. They don't all calm down though. My oldest male hasn't let me hold him more than twice since I got him over 8 years ago, not even a promise of taking his picture to show the online world is enough to get him to trust me, so I don't handle him, don't photograph him, just respect his wishes. The biggest suckiest crestie I have will come to the door when I open it, just in case I want to hold her. The majority are in between there - they'll sit still a while and then want to go back home. When they get antsy and start jumping, it's time to put them back. My leachianus gives a soft whistling type noise, like a loud exhale through her nose, enough warning to put her back. If I ignore it, she poops on me. A leachie can poop. You don't want to experience it a second time, so she knows she'll be back home once she lets me know. With cresties, you have to read the signals.
If yours is agreeable to handling, go for it. If not, then don't bug him/her, get another one to add to the collection. You'll eventually want a dozen of them anyways, so getting more until you have a calm one is okay.