The shutter button is not called a "shooter" and though it may be fun, a good photographer does not "aim" at her subjects (not unless you really do want to kill the shot... hahaha). Rather, the photo area is called a frame, and we are going to work on filling it with the subject.
Remember, we already talked about sweeping the background before you take a picture? Keep that in mind here. I'm going to draw your attention specifically now, not to the background per se, but rather your subject's head. Two questions:
1) Where is the person's (or peoples') head in the frame? Smack dab in the middle, or off to the side?
2) How big is the person in the photograph?
Unless you are shooting a special landscape or monument in the background, you want your subject to take up almost all of the room in the photograph. Don't be afraid to zoom in nice and close. The number one problem of amateur photographers is that there is too much distracting background, and not enough of the subject.
Also, very seldom do you want the person's head in the middle of the picture, like a bullseye. It should land somewhere near the top, without cutting their hair off (unless you intend to creatively do this... which can be very effective in face-only shots). Putting heads in the top third of the frame eliminates the problem of too much sky. I'll show you what I mean:
pic 1 (aim)
Whenever you are ready, post your fav. pic on your blog, mentioning the contest (or email it to me if you don't have a blog). Then simply comment on any of my photo-contest posts and let me know where to see it!