I would bet most people are afraid of failure, but what does that really mean, especially in an area as subjective as the arts? I've got some tips :)
* Think of art as a process, not a product. I've heard it said, "Art is never finished, only abandoned". Enjoy the whole journey and then learn to step away.
*Just start. That first brush stroke is the hardest. Thankfully, most paint is very forgiving. It's not final until you want it to be!
*Adjust. Think creatively. If a piece of art is not looking like you intend it to, change your intention! Turn it into something else. Sometimes the best creative discoveries come from what initially we think are "mistakes".
*Stay curious - Experiment with new mediums, new techniques and see what happens. Learn the elements and principles of design and try to apply them. If your art does not turn out "perfect", think of it as an education.
*"Fun Size" -keep a few small canvas boards handy to do "studies" - smaller versions of larger pieces. Try techniques out on a small scale first until you find what works for you, then take on the big project!