Arrange all the items used for cooking, so as to be easily accessible.
Label the containers for quick reference.
Wash vegetables before cutting to avoid loss of soluble vitamins and
minerals.
Peel vegetables as thinly as possible to preserve the minerals and
vitamins.
Do not throw the water used to boil vegetables.
Soak onion in water before peeling it.
Soak rice for a while before cooking.
The order of preference of food should be steamed, boiled followed by
fried.
To obtain maximum juice from lemon, soak it in luke warm water for a
while before cutting.
To reduce fat in the chicken, remove the skin before marinating it.
The thicker the fish, the longer is the duration of cooking it.

For more

http://usefulcookingtips.blogspot.com/2008/02/tips.html