I have been using Google Sheet to manage my freelancer cashflow from 2013, and I use to squeeze every year in one Google Sheet; every sheet represents a year until 2018. The amount of transaction is getting more and I going to start a new company, so I switch into 1 Google Sheet for every year.

The screenshot shows how I manage all the deals/invoices and transaction-related follow up actions. Each column represent data that I need to know for example
- Month: So that I can compare where the month that be quiet and what is the month I might need more resources.
- Company: Which client is this.
- Invoice: The invoice number.
- Project: What Project I m working on
- Sales: How much total amount of the project
- Upcoming: After the initial 50% how much more is pending
- Invoiced: The invoiced amount normally will invoice 50% before the project started
- Paid: How much does the client pay already.
On the most right-hand side, there is some summary column for me to check. How many sales did I meet, how far is it compare to my quarter target / annual target? Through the summary column, I can tell very fast how much more money are pending with clients, do I have any income next month etc.
Just thought of sharing this to fellows who start their freelance career.