By having all your fuel receipts together on December 31st, all you have to do is add them up one time. You are done. This holds true for all receipts. You will need to keep a spreadsheet or record of the expenses that are found on the settlement. Be sure you understand your settlements this seems to be an industry wide problem.
Every company has a different way of doing it.
Do not stick your head in the sand. It is your money we are talking about. That is why you are in this business. To make money. You need to find the ways that put more in your bank account not the IRS' or the company's.