How can I shape my muscles?!

How can I shape my muscles?

How can I shape my arms? I've been working out for the past 3 years and I really don't have shape to my arms or anywhere else...I workout with somewhat heavy weights and do about about 9 to 10 reps and about 3 or 4 sets of them. But now I really don't care much about muscle strength but more about appearence and shape...So do I just do lighter weight and more reps?

despite what most people think, it is actually not possible to "shape" muscles as your asking. most people think that by doing lower reps, u will add strength or mass, and by doing higher reps u will be able to shape your muscles. this is actually a myth.
if u want your muscles to be as shaped, there are only two things u can do. first of all, as you must know, your body fat percentage must be low in order to bring the definition of your muscle out (like your bicep). the second thing is that you must train train in the hypertrophy (muscle growth) range. this is generally 6-10 reps but i recommend 8 reps. this will cause muscle growth to occur. as your muscle becomes bigger and bigger, it will have more and more shape. then by losing the fat, it will really be defined.
all high reps do is make your muscles harder because of the glycogen it allows to be stored in your muscle.

this is the only thing u can do. trust me. i know what im saying.

and also, in order to make your muscles bigger, like i said, it is absolutely critical to eat a high calorie diet with lots of protein and even more carbs. you cannot put on muscle without eating a lot

however, the shape of your muscles are due mostly to genes...