Getting paid in dollars

Hi, I am working for an overseas startup. I get paid in dollars. For the last six months I have been getting $500 a month. Starting this month I will be getting incentives as well. It is below the salary for tax but I'm not sure how it works with an overseas company?

You are still required to submit a tax return in South Africa and declare the income on your tax return as other income.

What paperwork is required from my employer?

The American IRP5 (a document similar to the IRP5, it accounts for the income you earned and any tax they might have deducted from your income) your employer issues you at the end of their tax year is sufficient.