An unsung hero of invoices trails along at the end, the recap. Typically it lists in a table format each timekeeper who logged time during the invoice month, the number of those hours, and the billing rate of the timekeeper. A little multiplication leaves the final column that shows the total covered on the bill.
The usual recap sorts this data is alphabetically by the name of the timekeeper. An enhancement shows the percentage of the total billed by each person. More useful is a sort order by seniority of lawyer because the reviewer can get a sense of how the work distributed by level (partner, associate, paralegal, etc.). A variation would be for the recap to include a line for each level of timekeeper. The point is, give some thought to what you want your firms to provide in the billing recap.