@timeforawine,
There are some good internet pages so worth reading on cats scratching. It's very instinctive for them. The main triggers are eating, sleeping & pooing. Cats will especially tend to want to scratch right after or possibly just before doing those things.
Thus, ideal to have scratch surfaces that are right near where they eat/nap/defecate.
Some cats like to stretch UP to scratch. Some prefer to stretch ACROSS. need to observe which is your type of cat, and give them perfectly sited surfaces at the right orientation. Most cats like edges for scratching, to get their paws around the sides of it. It needs to be heavy enough that cat won't pull it over -- they are easily discouraged by something that falls on them So try to create heavy scratchable things with side edges near where they wake up from sleep or eat, either vertical or horizontal or both.
I made raised scratch boards covered with carpet offcuts because my main carpet killer stretches out to scratch. Carpet-killer cat is compelled to scratch within 1 minute of waking up, so important to have a scratch paid within 2metres of his favourite sleep spot(s). Since the boards have edges, they are somewhat preferable to plain carpet.
This has reduced damage to the stairs. CK-CAt still tears up carpets in one of the bedrooms if he gets locked in there for a nap (cue me tirading at kid who closed the door).
Cats can learn by copying you... I showed CK-CAT how to scratch the boards & he actually copied me. This did not work so well with Cat-2, though Cat2 does use the same boards, but he still scratches stairs. I put towels on the stairs to try to protect carpet on stairs, cats are creatures of habit so it's a job of always trying to nudge them into habit of scratching elsewhere. I have a big piece of carpet above the food bowls which cat2 sometimes uses (because he likes to stretch up for scratching). If I was any good at actually making things I would create some kind of special stair fitting extra-long scratch board that would be more attractive to Cat2 than the actual stairs are. hth