AmrThabet - Could you post up an image of the model without the diffuse colors on it? That would greatly help us to give you a more accurate CnC on the model.
Also include a front and Side view as well as a couple of perspective views, or close ups that you think need to be looked at. A quick turntable is always a good thing as well. Silhouette shots are also very nice to have as well.
The reason that I mention the front and side views is someone is bound to do a paintover on your image to help you on the form of the model. The reason I ask for a single color to the model (I prefer the green clay material myself) is that the textures will take away from the model. Now if you’re asking for both model and texture, then give images with both, but for now, you should focus on the models form.
Also, time on task in sculpting is VERY important. If you don’t practice, you don’t improve. Try to find the time every evening to sculpt for a half hour to an hour. Don’t focus on, say, a complete character or creature, just something small. An ammo pouch, a couple of sets of lips, a couple of noses, a couple ears, a couple eyes, a shoe, a shirt, a couple of belts, a hand, a foot, an arm (no hand), a back, a front.
If you focus on smaller things like this you should be able to “finish” them in an hour or so. You also wont feel overwhelmed with how much work needs to go into a complete project. It also keeps your mind fresh because you’re not looking at the same character over and over again for days.
Anyway, I hope this helps you out,