Remove porch furniture, welcome mats and any other items situated on the porch.
Sweep the porch to remove debris and sand. Pay special attention to the corners and the cracks between the porch planks (in the case of a wooden deck-style porch.)
Affix a garden hose to a power washer, then turn on the water supply and the power washer motor.
Power wash the porch to remove stains and debris.
Block the porch entrance with a chair and place a "wet paint" sign on the chair to prevent people from walking on the porch. The "wet paint" sign must remain in place for the next 48 hours.
Wait for 24 hours to allow the porch to dry following the power washing.
Tape off the wall at the point where the wall meets the floor to avoid getting stain on the wall.
Pry the cover off the can of outdoor stain using a flat head screwdriver.
Stir the stain thoroughly with a wooden mixing stick.
Screw a broom handle into the handle of the paint roller. This will enable you to stain from a standing position.
Pour stain into paint tray and move the paint roller back and forth through the stain.
Roll stain onto the porch surface in 3-foot sections. Start in the far corner and move toward the porch steps or a doorway leading into the house.
Wipe off the excess stain using a rag. Do this for each 3-foot section before moving on to the next section.
Wait 24 hours. After 24 hours, you can replace the porch furniture, remove the painter's tape and take down the "wet paint" sign.