I'm not sure but I think some ships have an in room, TV review. We were on the Fantasy (older ship) and didn't. I did go to the purser desk the last sea day and got a copy of our bill to review as I heard the line would be long the night before and day of leaving the ship. I reviewed and paid off the tab and only had a few things after that time on our charge. The bill was slid under our door that morning we left.
I have read suggestions on longer cruises to review your bill about midway thru the cruise to make sure everything is accurate. I guess it is easier to review half the bill at one time, if you get what I mean. We are going to let the charges ride on the credit card this time and just pay it off when the bill arrives at home.