I live on the second floor and I've found that a lot of dogs I watch, don't know how to walk up stairs. So far, the best thing I've found is to have them watch my dog do it and then they kind of learn, but that can be complicated sometimes. Any other tips are much appreciated!
We have a 3 story house so we HAD to get the dogs to go up stairs. We started with lots of treats, first on each step and then after completing the first set of stairs, and continued until they reach the point they will go up without fear.
Walking very closely behind them going up the stairs usually works or I would just try using treats :)
I taught my puppy by putting a small treat on each step. I praised her every step and repeated a few times until she lost her fear!
I would find out what gets the dog excited (treats, ball, rope toy, squeaky toy , ect) and use it to lure them up the stairs. With food, put the dog on a leash and work one on one. For example, using treats, encourage the dog in an excited voice to step into the first step, and when he steps into it, give him a treat and praise. Repeat on each step until he gets the hang of it.
My grand puppy wouldn't go up or down so I placed him in the middle of the stairs. It took a couple of times but after that and watching another dog he went for it.