Try creating a one page form for yourself or employees to fill out everyday.
If it's just for you doing maintenance work this summer, then that's one thing.
However, if it will for you as a supervisor, and for people you have working under you, you'll need two separate sheets.
So if it's just you, include some or all of the following information, pending suggestions from other CB users:
Start time, end time, duration of lunch break, requisite expenses (with receipts stapled on), tasks completed, date, signature. Then you can hand this information off to whomever is paying you, your business officer, or whomever. Just make sure they OK the format you will be using, and agree to trust you.
I've been keeping track of my hours in an Excel spreadsheet and invoicing clients in MS word. When I'm out and about I record hours in a monthly planner I use to also record scheduled hours. I track expenses by scanning receipts for each billing cycle and putting them all in one PDF file that rides with the invoice.
I still invoice on paper.
My end of the month receipts are all the original documents from vendors and originals from my carbon copy invoice book.
(I copy everything and retain one copy for my files for when the bills come in)
I know it sounds daunting, but using MS Access to create a billing and hours logged database is extremely effective. Each person that does a job (has an assignment) would have theirown unique log-in and they would log hours and the job title there. Once that is finished, the database can create reports that would save a lot of time for invoicing and the whole 9 yards (all hail the Scotts!!)
The program itself has quite a few really well laid out templates that you can work with to achieve what your needs are. It may take some time initially to get it set up, but in the long run - very worth it!!