leave it to me!

せる(まかせる) A casual word for ‘designate someone to do something.’ Often you’ll near it like this:まかせて! Meaning, ‘Leave it to me!’. Who’s going to wash the dishes? 任せて!   $$$
ねる(ゆだねる) A more formal word for まかせる. To leave someone in charge of a large task. (a murder investigation, a corporate merger)
託す(たくす) To entrust someone with a very serious responsibility. Unlike the related words 任せる and 委ねる, 託す emphasizes the weight and grave responsibility of the task at hand:If you screw this up, the country goes bankrupt. The factory closes. The criminal walks free.