Detach the unnecessary parts of the mountain bicycle. These include the pedals, seat and seat post, brakes, front tire, cables and handlebar. Use a screwdriver and wrench to do so. Every bike is different, so this will take some experimentation on your part regarding the size and type of screwdriver or wrench you will need to remove these pieces.
Loosen the stem bolt with a wrench, then remove the stem.
Turn the front tire fork around.
Reinstall the stem with the stem bolt, leaving the front tire fork turned backward.
Remove the handlebars from a banana-seat bike and install the handlebars backward onto the mountain bike so that they can be gripped from the front of the bike. Use a wrench to tighten the bolt on the bike stem.
Determine the correct height for your plow blade. Hold the homemade plow from the handlebars with your back straight and arms at your sides, slightly bent at the elbows. Now have a friend place your plow blade against the front tire fork. Have your friend mark the front tire fork with a wax pencil in the location where the top of the plow blade should be installed for the plow blade to dig into the ground when you hold the plow.
Drill a set of holes through the tire fork at the pencil mark your friend made. Use a carbide drill bit.
Insert the plow blade into the tire fork and thread the iron bar that comes with the blade through the holes in the tire fork and the hole in the plow blade. Tighten the blade on the tire forks with bolts.