Welcome to the forum. There is quite a bit of information on this site. Most notable are the 11 'sticky' threads that include tax information in the new member section that some forum members have taken time to create.
As with any business there is income to declare and expenses to write off. If you have been doing this for four years you should be keeping your income and expenses organized so when tax time comes it is easy to figure it out. I use one of those tax return computer programs that walks me through all the permitted deductions, does all the math, and prints/submits electronically all the paperwork.
Good luck and have fun.
Happily shopping Rhode Island and nearby Massachusetts and Connecticut