An important tip - if you’re a sea-level citizen, just walking up stairs can turn you into a wimp. Don’t forget that you’ll be getting almost 20% less O2 and you’ll quickly find out just how thirsty you can become after just finishing a pint of water due to the 8%-10% average humidity level.
One myth that has been broken - you don’t get drunk faster at altitude.
Traveled a lot between Florida and Denver back in the day and it’s quite tough on the body for the first 4-5 days there.
Oh, and bathe yourself in sunscreen if you even think about going outside - even if you’re still in ski gear.
Almost anything up in the mountains is still going have a lot of snow, but in Colorado you never know until you get there - and snow squalls can also come up suddenly on sunny days.