A few observations on your situation:
1. Since you are a single member LLC you have the option to file as a sole proprietor on your personal return rather than filing a separate business return.
2. Since there is no one withholding taxes on your income, the IRS requires you to do this yourself. You will have to estimate your taxable income each quarter and send in a check or pay online at IRS.gov.
3. You MUST keep adequate books and records to support what you put on your Sch. C (where your LLC income goes). You can hire a local accountant or get accounting software.
4. It does not matter if you make a profit or not as long as you have a profit motive and is not a hobby.
5. You prepare for tax season by having accurate books and records!