Creating Tip Product
You will only take this step once, then you will always use the steps below under Add a Tip to an Order.
First, go to Products > Add Product.
Now, create a POS product named Tips, then make up an ID and description. It is recommended to leave the price at $0.00 as every tip will be different, allowing you to edit on the take order screen.
Next, ensure that the POS doesn't charge your customer tax on the tip. Under Advanced Options, set Taxable to No.
Don't forget to save this product!
Add a Tip to an Order
From the Take Order screen, use the search bar to find the tip product you created.
Click on the tip product that appears in the drop down. Now, edit the Price of the tip product to the correct amount and click Add Product.
The system will not charge tax on this item and it will not affect the tax on any other item that is on the order.