I learned a trick which really helped me ...... relax!

See in the past, I could climb a very short hill or an extremely gradual hill, but the moment I tried to tackle anything long, I would start wheezing and huffing, and my heart would feel like it it was about to pound out of my chest, and my legs would burn ... and within minutes, I would have to get off the bicycle, catch my breath, and then walk it.

Now, as soon as my breathing starts to get even remotely rapid, I slow it down and take it easy ... and I can climb just about anything.

Once I got over that hurdle, then I could work on my speed.