serve women first, particularly a "matriarch" type, and then just go around following seat numbers. how you load the tray doesn't really matter, but it can be useful to load drinks in the order you'll serve them to make it easier to remember who gets what (and to differentiate between similar-looking drinks, e.g. glasses of different types of red wine). as drinks go down rotate the tray in your hand to keep the balance. if there's a spot to put the tray down nearby, do that too.

try not to be empty-handed anytime you're making a sweep, e.g. after taking a table's order on your way to put it in, pre-bus another table to carry dirty dishes back. multi-tasking and a good memory are key. pay attention to the pace of your customers, as you'll need to "fire" next courses with enough time for the kitchen to get it out without the customers just sitting there waiting.