Packing for a Colorado vacation is both the same as packing for any vacation but it's also different from most vacations.
The same
No matter on where you plant to vacation, you need to plan your packing before you begin. Think in terms of the absolute necessities. Every decent hotel provides shampoo and soap, so unless you need some special hypoallergenic stuff, leave shampoo off the list. If you're a man, your basics should include a comb (or brush), shaving gear, toothpaste and toothbrush, maybe hair spray and deodorant. For the ladies, take your basic cosmetics like brush and comb, lipstick and blush. But we're pretty informal here so you probably won't need a lot of gloss and eye makeup.
Second, pack light. If you're going to several different destinations, you don't want to have to waste time packing and unpacking and lugging around a lot of dead weight. For a week's vacation, I usually pack three pairs of shorts, two pair of "wash pants," one pair of dress pants, three or four short-sleeved shirts and a couple of nice long-sleeved shirts for evening wear. I can then do mix and match and come up with maybe eight different combinations. I think women can get by with the same number of shorts, a couple of pair of pants, four or five tops, and maybe two "dress up" outfits