Hi Debbie,
I'm assuming you'd google it and take the best of...
Here's a site that lists 8 tips including K-rich foods and prescription meds:
http://www.snow.com/for-her/altitude-sickness-tips.aspxAn old hiking tip to increase O2 intake is to periodically take "deepish" breaths, breathe out thru pursed lips, creating back pressure in the lungs which is supposed to enhance O2 exchange in the lungs. Some think it works, some think it's BS- it either worked or had the placebo effect on me, making me think it worked.
If you hyperventilate, you've gone too far...