My two techniques for hills.

1. Try to gauge the steepness and length. Take a guess at what a sustainable pace is and start out that way.

2. When I guess wrong, it's no shame to stop and rest going up a hill. I just stand and catch my breath and resume when I'm ready. I never walk, though. That's my challenge to myself. I can't remember the last time I walked my bike up a hill. It could be over 30 years ago. I stop as many times as I need.

I don't feel it's realistic to maintain cadence while climbing. If you spin while going up a difficult hill, I think you work too hard. That is merely my opinion.

Also, it helps greatly to be able to ride out of the saddle for at least part of a climb. I didn't do it for many years, and once I became practiced at it, I became a much better climber. I'm now a pretty decent climber. In fact, I'm so good that I'm lousy at riding on level ground and downhills. My cycling buddies always beat me on the flats and going down, but I'm as good as my strongest friend while climbing.