I currently have a temporary stairs and would like to add Treads/Risers and Skirts. What are the steps to do this.. I would assume that I take out the current treads. Add the skirts (3/4 by 12 by 14ft) on each side. Then Risers. Then treads. This sounds easy but have not done this before. Is their any problems to look for.?? This is my first post... Thanks a lot... John