I know that this post is old, but in case someone else comes looking for advice.
You could say that I have a fair amount of experience with the pred. I've done dozens of short courses for asthma, and I've been prednisone dependent on a daily dose for just under a year now.
I have pretty significant stomach issues. I have significantly less issues with prednisone caused nausea, vomiting, and heartburn when I use the Orapred liquid, which is what I currently use for my daily dose. If you're having a decent amount of stomach upset, it may be worth asking for the liquid. One thing to keep in mind, however, if you don't have insurance, is that the liquid is significantly more expensive without insurance. A months worth of pills pre-insurance was about 5 dollars for me, but a months worth of liquid was 50.
Other than that, you have to make sure that you eat when you take it, even if you don't feel well - I always try to have at least a large snack, if not a meal, with my pred dose. Usually something bready like a sandwich or crackers. Nothing with too much liquid, since the pred seems to pump up the reflux. I get pretty bad joint and bone pain with it on and off - my doctor recommended nutritional shakes, which help, as well as exercise, though you have to force yourself to do it when you hurt that badly.
I've been having a pretty upset stomach from it lately - as long as I force myself to eat something the instant that I start to get the 'I'm going to hurl' feeling, I'm doing pretty well. And you know, I wouldn't be taking it if the alternative wouldn't screw me up worse...I hear that breathing is important or something like that.