First we need more details. What type of gecko is it? How big? How big is your tank?

You can’t automatically handtrain a gecko. If you got the gecko from a petstore than it’s probably ripped straight from the wild.

To get the gecko use to your hand it’ll take a week to two weeks. First put your hand in the tank about 10 to 20 minutes a day (play with the substrate, change it’s water, who knows). Then slowly graduate to petting the gecko. Thereafter you should be able to put one hand infront of the guy and slowly CAREFULLY pick him up around the shoulder or armpit area (depends on what gecko you have).

Some geckos, since I am completely oblivious to your species at this present moment, are supposed to be just for show. Ie, you shouldn’t handle them much or at all. Some other geckos can be handled, but not more than 2 times a day. Keep this in mind.

House geckos are ’geckos just for show’ like their distant cousin species. If you absolutely need to handle the gecko, do so only once or twice a day and no more. The stress can actually hurt the gecko.

If you want to handle the gecko, then do the previous steps I gave of letting it get use to your hand. Don’t expect that it wont bite, because it probably will.