If she never done any stunt before, you might want to consider using a stunt double and then once in a while show the real actress in close up (without moving), and cut between, wooden stairs have the tendency to give a lot of pain and might really injure your actress during the 'flight'.
One thing I can think of is to use a small board under her, besides all the padding she is wearing, a small board size of her body, to be place under her to protect her from hurting her back, but if she doesn't take precautions, she would hurt her head by accidently hit the stair...
If you can edit between cuts, then you can get away with a wide angle shot of a double being dragged and all, then cut to close ups of her, and then from above her, showing her coming down (having a board and other safety stuff around).
And, if you want, shoot it in SLOW mo and speed it up accordingly during post.
I really say get a professional stunt person, because this is dangerous, but if you can't do this at your own risk, and make sure EVERYONE is comfortable with it. Do not rely on what the actress say (they always going to say it's fine and they can do it" trust their eyes but looking deep and you can see the fear...
Anyway, whatever suggested here are merely suggestion.

we don't want to be sued for any wrongly death or injury caused by our suggestion.

Do it at your own risk.
Johnny