Well, a few things jump out at me.
First your colors contrast too much, and that detracts from any visual appeal you would otherwise gain from a color standpoint. The Designs4U backdrop 'glow' blue is just a bit much, and not really needed like that, it's also not centered so if you were going for a motion-blur or a shadow glow of some sort, that's not what that would look like, so it just looks off-center.
The type-treatment, outer bevel / chiseled sort of effect, that's not doing you any justice, specially with the font size so big and overpowering.
It doesn't much look like a banner anymore, more like a forum signature, and even as that, you could really work on it to improve everything.
Add some texture to the background, less is more, so get rid of a couple strokes there that detract from the design and shrink the font, lose the bevel and go with something slick, not necessarily minimal, but subtle? Add a nice effect if you must, and if you like the glow then try to not use colors that contrast so much and just look visually awkward.
All that said, if you're looking to create great banner ad designs, here are some things to keep in mind when it comes to the banners content:
Spit thinks you're doing very well, but with some more practice you'll be creating banners that are many times better.
- You need great copy, a good punch line, something that will be worth reading. The companies name taking up the entire banner size doesn't tell anyone anything about what 'designs4u' offer.
- Relevant graphic elements if you want to add some in. The generic swooshes and lines are fine if you're going for an abstract design and focusing on the msg, but if you don't really have copy to add, as in content, then use a relevant illustration or graphic that tells people what the ad is promoting.
- Regardless of the fact that your banner will be clicked, it's important to add your logo and url someone in the design (just make sure it doesn't hurt your overall message)