FGH> PM sent
Since delsymfan already mentioned aclimating to altitude before venturing out, I have a few other basic pointers>
Bring a camelback with at least a 100oz bladder, its way too easy to get dehydrated at altitude.
Bring a lightweight rain suit as well as at least a good warm fleece pullover because temperature and weather changes happen in an instant.
Its also a good idea to carry small, sugary snacks since you will most likely not feel especially hungry, but you need to keep up your sugar and carbohydrate levels; altitude takes a lot out of you. I carry hard candy, granola bars and relion brand dextrose pills. Dont try to move at too fast either, keep at a comfortable, controlled pace while you are up there.
Try to be back below the tree line by about noon (if you get up above it), the thunderstorms pop up quickly and you dont want to be the most conductive thing up there.
Finally, its a good idea to scout out the area you will be in so you know what kind of terrain and wildlife you may need to deal with.
Dont take this as trying to scare you off, high country trips are among the best out there (some of my best trips have happened in rocky mountain natonal park), you just need to take some basic precautions
Hope this helps
Egor