At 38, just had my first colonoscopy. As everyone states, the prep is worse than the test. Here are a few tips I hope will help make yours a little easier.
1) try to schedule your appointment early in the a.m.
2) talk to your doctor about the prep. (mine was explained by the nurse who told me to take 1/2 the night before and 1/2 the next morning. Anesthesiologist nearly wouldn't do it because I had drank a liter of fluid after midnight and this is considered surgery)
3) go to the store and get what you need. 1 full day of clear liquids - you will want some variety. extra t.p., baby wipes, diaper cream, movies...
4) watch what you eat for 2 - 3 days. Saw a comment on-line to... eat whatever you want since you'll expel it anyway... two days before. Expelling hard to digest foods can be painful. The less you have, the easier it will be to expel later.
5) prepare the bathroom. Make sure it's clean, have extra toilet paper, baby wipes & diaper cream. I set up my laptop and had some movies to watch on it that made time much easier to deal with.
6) clear out unnecessary personnel. You really can do this all by yourself. Spare your loved ones the explosive experience.
7) just found out today that the moviprep I was prescribed can be mixed with other liquids. The package states to mix packages A & B with 1 liter of water and drink 8 oz every 15 minutes. When done this way, it tastes like saltwater mixed with lemon pledge. ICK. Apparently the medication part can be mixed with any clear liquid. My dad mixed his with Sprite, the nurse mixed hers with lemonade. Just be prepared not to want whatever liquid you mix it with again for a long time.
I am sure "set in time" varies. I started drinking at 6 p.m. finished the liter at 6:45 and was okay until about 7:30. I didn't leave the bathroom again until about 9:30 and wasn't completely done until about 10:30. You can use this time to use a little of the diaper cream. It will help slightly to ease everything through.
9) The next morning they told me to start the next round of prep at 7 a.m. My appointment was at 10. Could've started the prep about 30 minutes earlier. Longer if my drive to the hospital had not been less than 10 minutes. If they do tell you to do the 2nd prep the next morning, give yourself at least 3 hours from the time you start the prep to the time you have to get in the car.
For the test itself I was completely out and don't remember anything. I woke up without problem and was completely coherent as soon as I woke up. I was tired and slept for about 3 hours once i got home but wasn't wobbly or anything. (couldn't have driven though!).
I'm not sure if it's because they took 2 polyps, because they pumped in extra gas or what but I was not, am still not "starving" even though I got home 9 hours ago. A little New England Clam Chowder, saltines and ginger ale is about all the food I can handle. My doctor told me to eat whatever I want though. Hope this helps!