Having only ridden geared one or two times within memory, a tip I find really useful is for the front ring, small if you're going up hill, big if you're going downhill (and if you're doing neither then lucky you and make the best of it!). Then the back should kind of take care of itself.
I think I might have been grinding too high a gear at some points. I have a triple front and have to confess I dropped into the bottom ring for the final climb (21%!!!).
Having only ridden geared one or two times within memory, a tip I find really useful is for the front ring, small if you're going up hill, big if you're going downhill (and if you're doing neither then lucky you and make the best of it!). Then the back should kind of take care of itself.