Lay a plastic drop cloth on the floor in the area you will be working. Concrete can be tough to remove from surfaces once it dries so it is best to be safe and cover them.
Set the 5-gallon bucket on the plastic drop cloth. Mix a batch of concrete with the drill and paint stirring attachment.
Apply a thin layer of concrete to the wall with a trowel. Smooth the surface by holding the trowel at a 45-degree angle to the wall and pulling down in long, even strokes.
Press the decorative stencil into the concrete with the textured side against the concrete. Leave the stencil in place for 24 hours to allow the concrete to dry and prevent the stencil from leaving inconsistencies when it is removed. If you have a stencil you want to repeat, work in small sections and press and remove the stencil for each area. Or you can simply purchase multiple stencils.
Clean the edges of the stenciled area with a rotary tool equipped with a concrete sanding bit.
Vacuum up all loose debris from the concrete panel area with a handheld vacuum.
Paint the concrete or apply concrete stain with a paint brush. Use wax paper to cover areas that you don't want painted (or that you want to paint in alternative colors). Once the paint or stain has dried, remove the wax paper and paint that area in a second color.
Apply concrete sealant with a foam brush once the paint or stain has dried completely.