Ok, here goes. Dont get pissy because Im just trying to help you, you should take it as a compliment that I want to help you get the best out of your animations. ^_^
Make each movement less abrupt.
This can be done by-
a) Using the free transform tool, (the one that looks like a box) to make the person just lean forward that little bit more when his feet have stopped.
You need to do this for about 3 frames imo.
b) Making it all a bit slower. Not always the best choice, especially if you cant be bothered.
c) when he is flying, make him slowly reach a stop. As in, after the last keyframe of the tween youve obviously used to make him go up, click on the guy and make him go up by around 5 pixels (if they are pixels), then on the next frame make him go up by 4 pixels, then on the next frame 2 pixels, etc etc, (probably called something like a negative factorial, but who cares, it doesnt matter, its probably wrong, and you wouldnt understand lol) until he reaches a stop. Possibly you could make him rise by 1 pixel 2 or 3 times instead of just once. Also, once hes reached a stop, you could make him go down a small bit using the exact same method. (one pixel down, two piels, three, four) Of course, you have to ease him into a non-moving position again.
Also, dont use the blur so much for something so small. It just looks dirty, theres no real need for it because the guy is hardly moving fast, and if you were going to use blur you would just use it on the y axis (if it is the y axis, the one that goes up).Use glow instead, BUT- dont go overboard! 5 is an ok value for both x and y in this case (you could raise it to 10 at the most), and remember to turn the quality to high, so then it looks like the glow is coming from his "core", making it more mystical, lol.
Also, you know the problem with the head-
a) its lumpy, try and draw the head using only one brush stroke or using the circle tool.
b) he doesnt need to look down, at least not so much.
Im sure I could find other stuff wrong with it too, but I guess its not really that important, your just a beginner and its hard, i know.
But perhaps try a background. Zoom in a few times before you start drawing though, and use the second smallest brush tool.
Wow, I dont think Ive ever written so much advice in one post before!