The only way I have gotten any better on hills is by doing them. When I first started riding with the club (well at least attending the ride and riding solo as I'm not fast enough yet to keep up with the roadies on the Navigator) I couldn't do the hills. I now not only can do the hills, I'm actually stronger and a bit faster. Use your grannies if you need to and definitely gear down BEFORE you can't pedal any more.