workout help

So I want to workout so that I can grow my glutes. I've been doing donkey kicks, and firehydrants, for a month, with 5 pound weights.i go on the stair master at the gym for cardio.  I just have some few questions.
- how often should I change my workout?
- how often should I change the weight?
- how often should I increase the reps and sets? 
- what other kind of glute exercises are there, using ankle weights ? 
And I also want to lose belly fat. 
-what cardio is good for losing belly fat but not make you lose your glutes ?