To breed Hitmonchan/Hitmonlee/HItmontop, you must use a Ditto and one of the Hitmons, as Hitmon forms always remain male.
If you're breeding to get the egg moves for these Pokemon, you must breed the evolved form of a Hitmon with a Ditto, and then evolve the Tyrogue into the Hitmon you want to have the egg move. An example of this would be if you want Hitmontop to have the egg move Bullet Punch, you must breed a Hitmonchan with the move and a Ditto, and evolve the Tyrogue you bred with Bullet Punch into a Hitmontop.
Source: Experience