All those tips are good for high altitude, but beware sometimes you will react to the altitude differently. I used to ride in the San francisco bay area and would go to high altitude for races/rides a fair amount (Death Ride is one of them). Most of the time, I was fine; but one time I had altitude sickness when I went to do a mountain bike race (nausea, headache, general malaise) so just be careful if you start to feel bad when you get there. Rest and drink lots of water.