China is correct - frequent washing does strip away the sebavious oils that your scalp produces, and can make them go into overdrive, which will make your hair really greasy.
I would suggest washing your hair with shampoo every four days, using a nice mild shampoo - Pears or Johnsons Baby Shampoo are good. You can of course wet and towel your hair every time you shower to keep it feeling fresh.
Excess washing will not cause baldness - that is genetically programmed, and will occu,r or no,t depending on the trends in the family. If your dad and grandad on his side went bald, chances are you will too. When and if it happens, go gracefully, get it cropped and forget about it - no-one cares, neither should you.