To form curved concrete steps, you need to use a form. Typically, you use wood because you can shape it more easily than you can other materials. You need to build an outer frame and an inner form for the steps. To complete this process, use various pieces of wood that you find at your local home improvement store. Once you complete the form, you can pour and shape the concrete for the steps.
Using the shovel, dig out and excavate the area for the steps. Form the earth into the shape needed for the steps. Prepare the soil using a metal rake and compactor. Place 1 to 2 inches of gravel on the dirt as a bed.
Measure the width and depth of the step with the tape measure. Transfer the measurement to the 2-by-8 board. Cut the two boards to the measurement for the depth and one to the width, with the circular saw.
Place the boards together to create a rectangle shape over the step. Drive three screws into the corners where two boards meet, with the power drill.
Measure and cut the 1/4-inch piece of plywood to the height of the step. Place the cut piece of plywood into the 2-by-8 frame along the edge of the step, thus forming the step.
Measure the distance from the corner of the frame to the rounded plywood. Cut two pieces of 2-by-8 board to this measurement. Insert the 2-by-8 boards into the corner of the frame. These boards will support the plywood form.
Drive 2-by-4 stakes along the edge of the 2-by-8 frame with the rubber mallet. Secure the stakes to the frame with screws. These screws will keep the framing in place when the concrete is poured.
Repeat this step to create additional forms for the concrete steps.
Mix the concrete by following the instructions on the package. Pour the concrete into the form. Smooth the concrete by using the trowel.