From day one we should be keeping a log of revenue and expenses and weekly creating a income statement.
A daily revenue and expense log does just that.
We record all expenses as they occur or on the same day.
We record all revenue as it occurs or on the same day.
At the end of the week we total up all our revenue and expenses and then minus the expenses from the revenue. A positive total indicates were are in a profit and its magnitude. A negative total indicates we are in a loss situation.
This is our income statement or profit and loss statement or P&L.
These financial records can be kept on paper or using software. If software, don't forget to take regular backups.
These records will become more complex as our business grows. We will start breaking expenses and revenue down into categories and be able to analyse our income statement categories to be able to find areas that need improvement.