Here is how I track my work:
1) For every shop I perform, I have a worksheet. To it, I staple that shop's receipts. It then goes into a file folder labeled for the month and year of the shop. When the month transitions to the next month, I put that file into my file folder plastic box.
2) I created an Excel spreadsheet that records the pertinent data needing to be reported to the IRS. The spreadsheet has a top row with the particular month of the year in which I performed the shop. It has columns that indicate the week of that month, shop date, shop address, fee, bonus and reimbursement. Plus, for my own interest, I also added the date of the pay received. The fees, bonuses and reimbursements are totaled weekly.
When the month is finished, a paper copy is made and a hard copy is saved to my computer and a remote hard drive.
3) As for my mileage, I record in a daily planner my mileage for the day that I performed the shop(s). When the year ends (12 31), I file that away in all the other stuff for IRS information for the year.
It takes a little more time, but I know that if I ever get audited by the IRS, I have all of my records available. At tax time, I simply go back to these records to view the year's fees, reimbursements and mileage.
BTW, if I found money, I do not report it. Found money goes to two different areas - change to the Salvation Army, cash, into my pocket.