Learning how to climb stairs was one of Noodles's first challenges. There are lots of stairs in our house and even steps up to our front door. [On re-reading, it sounds as though we live in a very big house, which I can promise you we don't!]
In the end the solution was easy; we were out on a walk with his pal, Molly the Irish Terrier, and saw a bridge over a railway station with a long flight of stairs either side. Molly went on ahead and Noodles just followed without a second thought. We've found Molly very helpful in a number of situations like this and he certainly looks to her when he's unsure what to do or how to behave.
Noodles's current approach to climbing stairs is quite comical. He pauses for a moment and then flings himself up them at top speed, in a mad scramble. He uses the same method to go down as well. If anyone happens to be on the staircase at the same time they are mere obstacles in his path; he has been known to run directly into the back of my knees. How I haven't broken my neck is anyone's guess. J2 did break a toe and dislocate 2 others on Christmas Day, but that's another story!