How can i house train my pup?

Hi Moon! I think I would use a gradual process to get your puppy used to the stairs challenge. First, I would definitely make going up & down the stairs a rewarding achievement for the puppy- treats and praise for sure. Specifically for going down stairs, try one step at a time. I would get on the second step from the top & urge the pup to come to you with a reward in hand for each incremental step she may take. If you have someone who can hold the pup as she attempts this feat, similar to when you train a child to swim. If you don't have another person, than using this method really is the only way to get her used to going down the steps. She may wiggle a bit so it will be challenging, but if you have the patience, it should work with time and repetition. Remember to make the stairs and the potty time a rewarding and fun adventure, not a frustrating and angry task as much as you possible can. Good luck!