After you file

"A lot of my business is done in Thailand where there are no receipts and everything is paid with cash so I don't know how to submit for meals in that case." receipts are what the IRS would want and that's exactly what you don't have. the IRS could throw out every undocumented expense, pay a pro, they know how to negotiate with an auditor but it is still likely you'll be getting a tax bill from the IRS.