Your cash drawer is a bank type account. You spend money out of it the same as you would a checking account. To follow all the steps during a day you are probably ending and starting the next day with a counted and verified balance. All cash sales goes into the cash drawer and at the end of the day you deposit all excess into the night drop at the bank. At least that is what happens in a normal retail store.
Any money spent from the drawer during the day reduces the excess that goes to the bank.
Example. Start with $50 sell $100 running balance is 150. Buy lunch for 35. Balance is 115. End of day to keep 50 you deposit 65 at bank. Or to account for it just at days end you record a deposit of $100 in sales less $3/ cash back to the drawer, net deposit $65.
