First of all: study!
Read books (for example: Polished poker
by John A, forum member, try it, it's free!), post hands to have them analyzed, and participate in the community.
Secondly, if you're just starting, you should read up about bank roll management (Building from a baby bankroll
. Always have the discipline to stick to the limit defined by the bankroll that you have. Don't try to skip stages when growing into poker.
Be carefull about how you feel. If you treat poker as a place to escape the real world, it has the possibility to become an addiction. Take a break once in a while