We can focus on head accessories later on , right now we should design stuff for other body parts. Like tattoos , rings , shoes that look real , arm bands and how about clothing ? ( shorts , sleeves , socks ...).
I like what we have so far , once we have an item for every body part , we can make the shop . Remeber guys for each accessory , keep an editing file so you can adjust it if the buyer wants a different logo ,have a .gif file of the item ( leave the background blank so buyer can place it onto there texture and we can post it without a backdrop) and a .jpeg file.
One more thing , have two .gif files . The one texture will have no water mark and the other will (so we dont have to worry about people stealing them) . Try to make the water mark some what see through so people can tell what the item looks like .