Whenever someone asks a question this basic, I can guess they are not a very experienced archer. It would be best to visit a good archery shop and check out several things. First, the bow needs to be tuned, then you have to make sure the arrow is proper for the setup. Your arrow spine may be off, or some other factor that affects the flight. Then, you should have an experienced person look at your form and release.

Work on those 3 areas and you should see vast, quick improvement.