Keep drinking! It's VERY easy to dehydrate at altitude. The air is very dry so you breathe off more moisture. Also, your body adjusts to the high altitude by eliminating more water. Keep replacing it. SENE guides will keep reminding you to drink water - they know how much it helps, so drink up!
Make sure you eat plenty! Most people lose their appetite at altitude, but the cold weather and the long days mean your body burns through a lot of calories. Keep replacing them. You will need them. High carbohydrate foods are better than fatty foods. SENE will be providing you with healthy and plentiful food to make sure you have the energy needed to climb to the top. Eat it! It is freshly cooked and your body needs it, whether it feels hungry or not.
Keep warm! Take the correct gear because staying warm will lessen your risk of succumbing to altitude sickness. What should you take with you? SENE has provided a suggested packing list for you to consider. Some of these items can be rented if you aren't an avid hiker who will use them again and don't want to spend the money to purchase new items.
Keep your day pack light. Only take what you really need. Every extra pound needs extra oxygen to carry.
And last but not least, avoid alcohol, tobacco, and sleeping tablets.