I don’t do cocktails much, mostly because I don’t really have the ingredients around. One I like to do now and then is whisky (around half the drink, preferably spicy rye) and the rest about equal proportions of apple juice and ginger ale, poured over a chunk of ice.
Get somekind of workout and stretching routine going on. It’s much harder to build the habit later when you’ve got maybe a family going on and probably more work responsibilities.