How do you program tax in the swintec SW20 cash register?

To program tax in the Swintec SW20 cash register, first, enter the programming mode by pressing the appropriate key combination (often the "Mode" key). Then, navigate to the tax settings menu, where you can input the tax rate as a percentage. Save the settings and exit the programming mode to apply the changes. Always refer to the user manual for specific instructions related to your model.