Basically you find an extraordinary saint that was in a predicament or maybe has a talent or personality trait that is similar to yours and you read more about that person and then pray. A good way to find one is of course to just look at the huge list of patron saints and search for a while.
I've not found one yet. I once tried offer a prayer to St Genesius because he seemed like a badass but it was quite a halfhearted one so he might dislike me now.