Not only will you feel better if you walk everyday, you will make some pretty spectacular physiological changes which can lead to a happier, healthier life (and give you the strength, stamina, and mental clarity that would be very useful if you do end up facing a major disaster).
So your second task (after starting your emergency fund) towards becoming prepared for anything is to commit to walking everyday.
- Walk 30 to 60 minutes a day; preferably outside in fresh air on a variety of surfaces with hills and flats (barring that possibility, a treadmill would be OK).
- Get a good pair of walking shoes (although any pair of comfortable shoes will work, if you are serious about walking, shoes made specifically for walking will make a huge difference in your comfort).
- Dress for the weather (obviously)
- Find a walking group if you like (like this one)
- Set some walking goals (X miles per day/week/month)
- Take a small daypack with you if necessary (to carry your wallet, keys, bottle of water, etc)
- Be aware of your safety at all times (cross at crosswalks, beware of walking in secluded areas alone, maybe carry a walking stick or Mace to fend off dogs, etc)