Make sure you're on YOUR PROFILE. To the left of your profile pic, you'll see a "my stuff" link. Click it! (see below)

Now select "EDIT PROFILE" from the drop down. (see below)

Select the "customize Design" option. (see below)

Select "create Your Own Layout" (see below)

Select "TEXT" (see below)

Choose your font! Also, look below on your profile, you'll actually see your changes right away. (see below)

Now, pick the colors of your choice (normal color, highlight color, link color etc) (see below)

NAME & SAVE! You will now have a sweet background, and a nice color scheme! YAY! SUCCESS! You're now done!