Pretend they are bushes, at ground-level, and prune them as if they were. They should do just fine.
They are, after all, bushes, grafted to the top of that tall stem.

Jeri in SoCalif

Guess I am looking for things like, how much to leave on, how to shape them, etc....everything here is budding out fast and early, so i want to get them done before they leaf out and I don't want to cut off the new growth. Maybe if I had miniatures it wouldn't scare me so much but most of what I have are HTs.

Experiment this year and see how they come out. When I grew tree roses I pruned and shaped using a pair of manual hedge trimmers. I then went back over them with my pruners, removing crossing canes and anything damaged or dead that the hedge clipper missed.
For your first time, use caution. Remember you can always take off more but once removed, it's too late!
With miniatures, you'll have a lot of tiny canes so don't get carried away removing them.
Maybe this year, you'll just want to shape without removing too much. After the first flush you can go back and do more pruning or shaping if you think it's necessary. Roses are very forgiving.

thanks. I ended up shaping them (the Hocus Pocus had gotten straggly) and taking about half off, keeping the round shape. They are a new experience for me. I spent an hour and a half the other day pruning 18 HTs and while I am comfortable with them now after 3 years, the trees are not so comfortable.