Hi Angel,
 
Other than being self-confident here are some ideas,
 
Write a short how-to book...you could self-publish it
Make sure you have a professional website
And of course be good at what you are doing (or have a good
product to sell)
 
I read the 4-hour work week a few months back and he had some
ideas in that book, the only one I remember is getting
speaking gig at a University on the topic so you can reference
that and promote yourself that way.
 
Hope this helps.:)