hmmm. well i would think you could do of course a round cake.. ice it in buttercream and then make the black and diamond decorations with colored fondant.. and for the silver if you have a steady hand make some royal icing and make the lines and little dots then let that dry and paint it with some silver luster dust?? I say this like a question.. because I have never done a drum.. hope someone else has more detail info..
You can start with a round cake. Ice the top white and sides black. I think cutting the diamonds out of colored fondant is a great idea. If the royal icing thing does not work for the silver part...I would just use a grey icing and use a tip 3 or 5. Maybe for the dots you could use the silver dragees. I think you do not have to be exact...just get as close as you can...and people will get the idea. I think you will have fun with this one...don't stress out!!!
This might help if you want to try and pipe the silver parts:
I say do like a MMF type top becasue that is close to the texture or look of a drum. IMO