I've gotten several comments about how I change my blog. I designed my header image on my own, but the color schemes are really easy to do on your own too.
To change your header, from your dashboard, click "layout". Choose "page elements", in the Layout Tab. You'll see a box that says "Header" with your blog title in it. In the lower right corner of that box, click to change your banner look. This will bring up a pop-up window.
In the new window, you can change the title of your blog as well as the blog description. This is also where you can make your banner image different. Play with it to get it just right!
To change the color scheme of your blog, choose "fonts and colors" under the Layout tab. Now you should see a menu that displays all the colors of the layout you're using and a preview of your blog underneath.
From here, you can change all the colors of your blog. I find that the color options provided are very limited, and the charts online only provide so many color codes. So I use www.colorpicker.com to find the exact color I'm looking for. Play around with the colors until you find the perfect fit for your blog. Make sure you SAVE before moving on!
Good luck! And have fun!