Your missile seems stylized, are you modeling it from a reference picture? If not then I would suggest you decide what kind of missile you want and find pictures of it on google, av, etc. To me it looks a bit like a scud missile (just from a quick image search). With a reference picture, you can add all the little details that we forget when we’re doing something completely from our heads. If you don’t know how to put the reference image in blender you use view -> background image while you’re in 3D view.
The reference picture should also help you with any texture you choose to put on it, and to decide things like the spec value more accurately.
I’m not very far along using blender myself. Good luck to you on your project.