So, I'm currently working on a website of my own. Below is a small preview of what I designed. The banner is the problem as I'm not so hot with rendering. If you know how to render, please help me out. IMAGE DELETED
I'd say open the image in Photoshop and use the Polygonal Lasso Tool. That's honestly the best way if you want a quick and clean cut. If you'd like I can do it for you.