It all depends on where you are at. Some mountains are ascended by merely hiking to the top. Then there are others that require ropes, ice climbing skills, crampons, and ice axes.

The book that is the bible for mountaineers is, Mountaineering - The Freedom of the Hills. In this book you will find how-to information about climbing fundamentals, gear, survival, route finding, rock climbing, and snow and ice climbing. In either case, the mountain is never conquered, you are allowed to join it in its majesty above the clouds. Its primary weapons against vain challengers are the weather and the altitude. Your only protection,should you be percieved a threat, against the weather is your gear, and your ability to take shelter or retreat. There are a few things you can do to save yourself from the altitude.

Altitude
It is the mountains over 8,000 ft that seem to have the most power over mortal man. The affliction of altitude sickness comes upon you like a bear jumping on your back. Your energy is zapped and magically dissipates. Your stomach gets nausious, and your head starts pounding. The best way to prevent this to maintain a modest attitude when at altitude. Honor the mountain with each step. Stay hydrated by drinking fluids throughout the day. Never wait until you are thirsty. The altitude can also have the effect of curtailing your appetite. Try to eat a little every so often, even if you aren't hungry. The bear likes to prey on the weak, so stay hydrated and fueled. 

Acclimatization
Some of the aspects that affect how you will acclimatize to altitude are your conditioning level, the altitude, and the humidity. It might take 2 to 6 days for your body to adjust to its new environment. A way to check for your acclimatization is to take your morning pulse rate for some weeks prior to departure. This is to establish your baseline. Once you arrive to race location, take your morning pulse rate and compare. When the pulse rates seem to be equalized, you are ready to race. A quick caution about acclimatization, tropical areas may require just as much time to adjust as altitude.

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