If activated (see Configuration / Ordertypes), after pressing "Delivery" the pre-arrange tender screen will appear.  This screen allows you enter the expected tender type for the order.   If you are using integrated credit, you can authorize the card at this time. 

Select the tender type to tender the order.  For credit, type in the card number and expiration date in the pop up box.  If you wish to tender less then the amount due with this credit card, select the "Amount" field, press "C" on the keyboard to clear, and enter a new amount.   If you enter more than the amount due, a tip will be assumed.  If you enter less, the pre-arrange screen will remain after the card is processed so you can tender the remaining amount.   If you exit this screen for any reason, any pre-authorized credit transactions will be voided. 

To split the transaction into multiple tenders (non-credit) just touch the mutliple button before selecting the tender.   You will have the option to enter the tender amount.   Press SUBMIT when you are done.