1. Record the sales revenue of catering companies, including the amount of all catering sales such as restaurants and takeout.

2. Record the costs of catering enterprises, including all costs related to catering sales, such as depreciation of raw materials, labor and equipment.

3. Calculate gross profit, that is, sales revenue minus cost. Gross profit can be calculated by the following formula: Gross profit = sales revenue-cost.

4. Record gross profit in the voucher.