I’ve done this a few times, using excel. Last time was most challenging, because it was a cruise, with a few days using one currency, then a different currency during the cruise, then back to the original currency. A bit of a mess with currency conversion.
Here’s how I set it up:
When you receive the itemized bill, put initials next to each meal/drink. Note how much you added for tip. Also pay attention to any fees for using a credit card. Take a picture.
In the spreadsheet, create a column for Food & Drink, and another column for Tip & Fees. Calculate the % that the Tips & Fees represent (let’s say 25% for ease). Add a column for Food & Drinks + Tips & Fees.
Then create a column for who paid, if it might vary from meal to meal. This way you know who the money goes TO. Ignore this if YOU will always pay.
Creat a column for each person’s food & drink (including yours). In this column, add the food & drink amounts. Add a second column for that persons Total. This column will be the Food & Drink total times 1.25.
Sum each person’s column.
Add a column for the grand total. The grand total should match the Food & Drinks + Tips & Fees amount.
At the end of the trip, if you paid for everything, each person owes you the amount in their total.
On a previous trip, I maintained a similar tracking when traveling with another family. We swapped paying for meals, to keep it relatively even, and maintained a running total. We were off by about €20 in the end.