To make an armed concrete ladder you will need to have boards and boards so first they could shape the formwork (Building a Reinforced Concrete Ladder with Visual Help). You also have to provide corrugated iron from 10 to 12 mm diameter. Place some boards on one side of the ladder to do the stakeout. Once the ladder is marked, you will have the starting and disembarking place of the stairs. With a meter we measure the distance we have from the start to the landing of stairs.
Two planks of 15 cm. and wide 5 cm. we will make the strings. These should be 15 or 20 cm. Next is nailing a board to the floor and fixing the strings to it. The next steps are delivered in the link bellow. The gallery will help you visualize it and the guidance how to make this stair functional.