I'm not a person to go to for income tax advice. ;-) I'm just the artist. But I can tell you I file once a year with something called a "schedule C" which is when you itemize everything and get to write off business expenses. Then I can break up payments to the IRS quarterly. And really you can send the IRS a post-it with your name, SS#, what the money is for, and a check. If someone does your taxes for you they can give you payment vouchers to send in with payments.

In addition to mileage, write-offs can include working lunches, cell phone, home office purchases, office/art supply purchases, research purchases (like books), as a graphic designer I can claim software and hardware purchases, business website hosting expenses. I use my home phone and internet connection for my job, so that is also a write-off.

If you make less than $600/year doing this, then you don't have to file.

Resale is a whole different ball of wax.