1. Click Settings.
2. Click Taxes & Checkout.
3. Toggle the Enable receipt signature on screen switch.
4. Click Checkout.
5. Select the customer. Then, proceed with the normal checkout.
6. Swipe the customer's credit card. Click Next when you are finished viewing the message confirming the credit card purchase.
7. Select the percentage or enter the dollar amount for the tip. Use your fingers to draw your signature on the screen. Tap Charge Card to complete the transaction.