1. Click on the '+' icon located next to the main search bar in Workshop Software and select Customer Payment from the dropdown menu:

2. Search for the customer and double click to select:

3. Click on the green search icon to bring up a list of invoices with outstanding balances:

4. Click on the invoice to be paid and then click on the green 'Select' button or if you wish to select all invoices then click on the blue 'All' button:

5. Enter the payment method and click the green 'Apply' button to apply the payment and then click 'Process' to process the payment: