Remember Quality.....quality....quality.....! 

Next - an original idea is always the best....research.

Go to the wish forum, find out what others are asking for.
 
Don't steel from others, keep it originally from you.

One more thing....don't always count your time as part of the cost you place on a product. You will find you put alot more time into something then what you can really charge for it.
 
Don't take critisism personally.

Does that help?  Sharen