well it's easy when it's winter/fall then you just layer,but in the summer...that's a bit of a challenge to make it interesting,since it's usually supposed to be simple and as tiny as possible. go through fashion blogs,magazines,you'll get inspired. I like this link blog,this dude takes pictures of well dressed/badly dressed people in the street and comments on them,and most of these people have very interesting clothes,even if you don't get inspired you can get a laugh out of some of the freaks he finds
Anything black or gray with a pop of color like red or bright purple would look nice layering may work too, putting a shirt on top of the other may make it look like a whole different piece of clothing. Hope it helps.