I've been doing WW for a long time and i've always used weeklies first. Mostly because that is how it's always been, ya know? Some people prefer to use fitpoints first because those are earned points. It really doesn't matter which you use first, but it's not ideal to use both. In other words, i get 30 daily points, 42 weekly and earn 21 fit points. You shouldn't use all 63 extra points.