I'd second the idea of shaving your head if the chemo will affect your hair. The chemo won't affect you right away may even take several weeks, so there is no hurry to do it right away. My wife trimmed her hair to only a few inches long but found that even that irritated hair follicles. At the very least i'd recommend a close buzz. Not sure about facial hair, the wife never had to worry about that haha.
Don't worry about the weight, it might be a blessing in disguise. My wife had to take steroids the day before, day of, and day after chemo and those days she ate like a horse. The other days in between were hit as miss. Some days were nothing more than light snacking while others were quite normal.
I'd also recommend that anyone you see on the regular basis get their flu shots. Chemo will knock your immune system back a bit. It's just one less thing to worry about.
Haha I'd like to second this one too. I had my first colonoscopy last year. I was having lower abdominal pain which luckily is just tied to poor mechanics in my hip. Fortunately for me though the colonoscopy did find a polyp which was easily removed during the procedure. The polyp ended up being nothing but if left long enough polyp's will eventually turn cancerous. I'll have to go again when I'm 40 but that's no big deal. Like you said the colonoscopy itsself was extremely easy. They didn't even knock me out, just a local anesthetic I guess. I was watching the screen and talking to the doc they whole time. No discomfort at all. The day before prep sucked but it nothing worse than a stomach bug.