1. Click on the Administration Tab on the left side Navigation panel and then click on Settings Tab.
  2. Click on Common tab and scroll down to tax percentage.
  3. Enter default tax rate in the box in numbers.
  4. Select in between Tax Inclusive or Tax Optional.

*Tax Inclusive is that all your charges are after tax included in them.
**Tax Optional your Tax is optional and is not included in the price if charged, then charged separately.