One sees different advice on this thread. If one looks at it more closely, one will see that more experienced riders advocate lower gears and higher rpms, while less experienced cyclists advocate the opposite. There's a reason for this: it takes a lot of practice to get any good at all at putting out power at higher rpms. When I first started serious climbing, it felt to me as though I were peeing strength out of the bottoms of my feet if I tried to climb at any cadence over about 80. Now I can climb comfortably at 95. It comes with time and practice, and you will find, as your conditioning gets better, that you will climb faster and for longer with a higher cadence. I favor 78 for very long climbs, and higher cadence for shorter climbs, though everyone is a little different.

Our touring tandem has a granny of 26-34. We climb at about 4.5 mph with that gearing, much faster than walking.

If you want to figure out how your gearing works, what you do is to create a spreadsheet with your gearing. Put the teeth on your chainrings in the left column, and the teeth on your cassette across the top. Understand that the measure of gearing is called "gear-inches." This is defined as the teeth on a chainring divided by the teeth on a cog times the nominal diameter of a wheel, so 27" for a 700c and 26" for a mountain bike and 20" for a Bike Friday and some recumbents. Your SS will look like this one which I did for our tandem, except with different numbers:

[table="width: 500, class: grid, align: left"]
[tr]
[td]Rear[/td]
[td]Teeth[/td]
[td]12[/td]
[td]14[/td]
[td]16[/td]
[td]18[/td]
[td]20[/td]
[td]23[/td]
[td]26[/td]
[td]30[/td]
[td]34[/td]
[/tr]
[tr]
[td]Front[/td]
[td]52[/td]
[td]117[/td]
[td]100[/td]
[td]88[/td]
[td]78[/td]
[td]70[/td]
[td]61[/td]
[td]54[/td]
[td]47[/td]
[td]41[/td]
[/tr]
[tr]
[td]Front[/td]
[td]39[/td]
[td]88[/td]
[td]75[/td]
[td]66[/td]
[td]58[/td]
[td]53[/td]
[td]46[/td]
[td]41[/td]
[td]35[/td]
[td]31[/td]
[/tr]
[tr]
[td]Front[/td]
[td]26[/td]
[td]58[/td]
[td]50[/td]
[td]44[/td]
[td]39[/td]
[td]35[/td]
[td]31[/td]
[td]27[/td]
[td]23[/td]
[td]21[/td]
[/tr]
[/table]
The numbers from 117 in the upper left down to 21 in the lower right are the gear inches. Of course you are seeing the formula results, not the formulas, and this is a 9 speed setup with a triple in front.

What good is all this? Well, this will show you how I use our tandem's gears, and how you might use yours. As a hill steepens, I usually run the big ring down to 61 or 54 gear-inches. Then I shift to the middle ring. Thus I don't use the two smallest cogs in the middle ring, nor the two largest cogs in the big ring. Then I usually run the middle ring down to 35 gear-inches. Then I shift to the granny ring. Thus I don't use the largest cog in the middle ring, nor the 4 or 5 smallest cogs in the granny ring. You can also see that if we were cruising on the flat, that the higher gears between 88 and 54 gear-inches are not exactly duplicated between the big and middle rings. Thus if my cadence is a little too fast or slow for my liking, I can find a slightly different cadence at the same speed in the other ring. This is on purpose. I used this spreadsheet tool to select this cassette for use with these chainrings, thus these gearing combinations.

This may seem a bit too geeky for many, but if you study it, it makes a lot of sense and is worth doing. In the old days, people would tape these gear charts to their stems.