To keep track of the sales of the fundraiser you have many options and you can personalize them to your style of restaurant. Some examples are below:
Fast Casual/Quick Service
At your pay counter, you can use a personalized box or basket and have the guests drop in their receipts. An alternative option is to use your POS system to track the tickets contributing to the event.
Sit Down Service/Casual or Fine Dining
Have your servers that day informed and ready for the event. They can either collect receipts copies in an envelope, turn them into the MOD, or mark them on the POS system. Whichever manner you decide, please make sure your staff is well prepared. The groups will identify themselves with the fundraiser, so it is important for all of the staff to know what group is hosting a fundraiser that night.