=3 Good job on your first time. Excellent work on drawing the auto mail. That is by far the hardest part of ed to draw XD. If you want I could give you a few pointers to make the auto mail pop out a bit more and look more metallic =3. But up to you.
Well first off the auto mail is reflective. So there are gonna be some high highlights on the side that is picking up the most light. With that the other side would be darker then normal. And you should keep the base color the same and where the plates intersect or layer over one another you use shadows to make the plates pop out from one another.
=3 If I get time this weekend I can do a mock up on what can be done.