You tip your waiter on the last night of the cruise as you are getting up from the dining table - at least that is what we do. He will no doubt have a packet of all the menus for you - get him to sign it when he gives it to you, unless of course, he has already signed it.
If you are ging to eat in the Lido that night, I would suggest giving him his tip on the last night that you will be eating in the dining room.
You tip for room service each time you use it.
Bar and wine stewards can be tipped each time you order a drink or bottle of wine or you can tip your favorites the last night of the cruise. In this case you will have to go around looking for them. We tip the wine steward in the dining room on the last night of the cruise. Don't worry you won't have to go looking for the fellas in the dining room - they will be around somewhere.
Any more questions, please ask.
Where is your cruise to and what ship and when?