While never competitive, we used to train our dogs for agility contests. Baring age/other infirmities, take a bit of time to train them about the steps. With a leash on, and the dog at the bottom, place a treat on the first step. The more desirable, the better. Let them get it. Repeat a few times. Put on the second step, and repeat. And so on. As it gets further away, if they have a tendency to jump steps, use the leash to prevent them from getting to the goal, and use a mild voice correction - ie, they get the treat only walking up each step. It helps, of course, if your dog already has a solid "wait" command - don't do anything until I give permission, but is not a key for this process. Take it a bit slow, and make sure they are repeating the climb correctly each time.
Same process for going down - but work a lot more on the always-one-step-at-a-time expectation. In agility, it is usual for dogs to launch themselves off a steep down going ramp to get to the bottom (treat) or next adventure, which is when injuries happen, so be rigorous. Spend a lot of time repeating with a final treat at the bottom, which they only get when going down correctly. Never, ever allow them to get away with a jump.
First down step can be scary, so perhaps a start with sitting in the doorway looking out, and treating. Then extending the treat out and down a bit so they stretch for it. Then finally on the first down step. Once they get that that one is good, the rest will go very fast.
Our old trailer had punched out holes for treads on the steps, that the dogs hated (probably uncomfortable to step on) - Camping World, etc. sell strap on carpet that goes on each step, that resolves the issue for both dogs and barefoot people.
None of this will take very long - dogs get it in only a few sessions. It's not as tedious as "intellectual" commands like down, stand, or heel.....
