The Halloween experts at DIY Network have instructions on how to make a spider costume.
Thinking about a Halloween Spider Costume? Check out the Hairy Tarantula Halloween Costume: uses foam for shape so this spider costume is flexible and comfortable.
costume tarantula if you feel really ambitious:) Haugen Haugen McClintic
Cheap almost free DIY costume idea: Add any white string or thin ribbon over a black skirt to create a spider web pattern!