Gradient Help!

Hey guys, I just downloaded photoshop cs6, and I was creating an image for a project I am doing. So, I have Red, green, and blue, I was to have 3 gradient colors. How can I do this?

This will help.

When your go on your gradient tool there is a bar at the top showing the gradient. Click on that, and where it shows the colors click someone on it to add another one.