On Carnival the first test was to see (I think they do it now automatically) is if he could bring me a sheet across the whole bed that they would have to get from the suite room supply. If that was done with no problem (one steward told me no way) that was an automatic extra tip. After that we LOVE ice. We ask that it is not ever empty. We bring beer in the bucket to the room and that is iced and the wine is iced without asking. One cabin steward decided that my bon voyage gift of 24 Coronas needed to be cooled down in a refridgereator so had maintenance deliver one to the room and set it up for my use for the week...
Various things. One steward gave us a wooden hand made cross his wife made when he went home to see family in Cozumel. We always talk to the stewards and find out about their families etc.
One gave me the creeps when he introduced himself and looked into the cabin behind me and asked "Are you traveling alone????"
Luckaly hubby talked to me on the radio then and I said "no". But he did turn out to be a good cabin steward even though I didn't feel very safe around him.... Debbie