You will need to file Sch C ( Sole Proprietor).
I suggest you ckeck out IRS Publications 334 (Tax guide for small businesses), 463 (Travel , entertainment and car expenses), 583 (Starting a business and record keeping) and 587( business use of your home)

http://www.irs.gov/publications/index.html

Once you get a handle on your estimated expenses, 20% of you estimated net income might not be enough DEPENDING ON YOUR ESTIMATED GROSS INCOME. I suggest 25%, not knowing your estimated gross income.
The 25% bracket for singles in 2007 begins at taxable income of 31,850. Add to this the 12+% of Self employment tax and you can get to signifcant rates at a relatively low income if you are single.

My guess is that your net will be probably 70 to 80% of your gross.

So, earnings x 75% x 25% ought to get you in the ball park.

If all you want is a safe estimate, take your 2006 total tax, pay half on June 15 and the balance in 2 equal installments 9/15 and 1/15/07. ( Of course you will owe much more come April 15, but you've had the use of your money.)

At least you have no state income tax to worry about in FL.


College tax courses don't teach much imo.