I tried several different ways to invoice, and the most effective has been to buy Sales books from NEB and write one out by hand at the end of every job. 99% of the time, I get a check on the spot, so it helps cash flow, eliminates billing problems because any questions are answered on the spot, and avoids forgetting to send an invoice or letting too much time go by before sending one. Most of us love our work but hate paperwork and often invoicing suffers because we put it off for one reason or another. Or, maybe it's just me! I've been doing this for 20 years and have found that invoicing has always been a problem for other consultants I communicate with.
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