How to Make a Ninja Costume. The ninja costume is easy, and it has a million uses. For young ninjitsu enthusiasts or adventurous role-players, getting yourself in character requires just a few basic steps. But the ninja, mysteriously cloaked, can appear dangerous. Let others know that you're a friendly character underneath the ominous costume.
Pick a color. The classic ninja is clothed in black, but other colors will do. White ninjas are not uncommon.
Find clothes that match. What you'll want is simple, unadorned clothes with no obvious brand names or slogans. A pair of black jeans are perfect, and a cotton shirt with sleeves.
Get inconspicuous shoes or sandals. You probably don't have anything close to what old-school ninjas wore, but the best bet is a pair of shoes or sandals that match your clothes and don't have a brand name written on the side. Try to avoid give-aways like the Nike Swoosh that detract from your authenticity.
Wrap up your head. Take your colored scarf and wrap it around the top of your head once or twice. Then, wrap it around your jaw and neck, and pull it tight. Pin the scarf together so that it won't fall, and you have your ninja mask.
Attach the rope to your waist. Although a ninja often doesn't need rope, it's a good accessory and might come in handy.
Find ninja accessories like swords, bows and throwing stars. All kinds of ninja objects can be found on sites like martialartsgear.com, from grappling hooks to stars and other traditional eastern weapons.
Be a peaceful ninja. Countless newspaper articles demonstrate how an overzealous role player gets into trouble. Practice your ninja skills in a safe, non-violent way.