Here are a few important tips excerpted straight from The Doctor's Protocol Field Manual:
TIP No. 28 – The absolute best food for emergency prep is canned soup. It's the main surplus food supply I keep in my own home. It's compact and easy to store. It will give you all the nutrients you need. And it keeps for a long time.
TIP No. 44 – In addition to having enough food stored to last through a severe blackout, it's also important to have backup methods of cooking. Eating cold soup during [an emergency] isn't great for morale. I recommend keeping a small metal stove and a backup supply of fuel tablets or Sterno fuel. Camping goods maker Coghlan's sells a folding emergency stove along with 24 fuel tablets for less than $10.
TIP No. 50 – Five-gallon "water cooler" jugs may be the easiest and most economical way to stock up. One-gallon jugs may fit better into available shelving. I keep about 10 of them filled in my house at all times (three in the freezer).
TIP No. 62 – If you are trying to keep warm, apply as many layers as possible. Your body stays warm by heating the air trapped beneath the layers. Stuff crumpled paper into your pockets and in between the layers. The extra insulation provides more air pockets to trap heat.