I think it depends on how convoluted your splitting is. To make things easy, my friends and I tell a waitress individual checks up front, then the couples will

I think it depends on how convoluted your splitting is. To make things easy, my friends and I tell a waitress individual checks up front, then the couples will tell the server "pay these with this card." That is much easier than saying "these 3 on this bill, these two on one, these two on antoher, and three individuals."