You will come across transactions where you need to pay with multiple payment methods (or tenders as they are sometimes known). Check out the procedure below for more detail.
If you need to split a payment between several methods, you just need to type in the amounts you want in each payment method.
Be aware that once the "Amount Due" the the bottom is $0.00, it as if you clicked the OK button, so be sure you have the right amounts in place.
There are times when a customer will have multiple credit cards or gift cards. To put different amounts in for each card, click on the button on the right side of the payment method.
Then, enter the amount in the new space provided.
If that button does not work, it is likely not set to allow this. The setting is in the Back Office of Cloud Retailer under Admin --> Payment Methods. Be aware that this ability might be turned off for a reason, so check the policy of your store before making a change.
Here is a video showing all of the above information: