A one-page monthly check-in sheet that tells you if your business is actually healthy. Fill in 8 numbers at the end of each month: total sales, total expenses, profit, number of new customers, number of returning customers, stock value, amount owed to you, and amount you owe. The sheet does the rest — shows you your profit margin, customer retention rate and whether you're growing or shrinking. Comes with a plain-English guide explaining what each number means and what to do if something looks wrong. Print it monthly, keep it in a folder. Simple.