Halloween is a devil's holiday, not a Christian observance. The founder of the church of Satan said that by dressing up, either by wearing a costume or coloring oneself for Halloween, is tantamount to worshipping the devil.
How do you attach a devil tail to a dress?
https://www.youtube.com/watch?v=Zmc-3SFYpqI
How do you make a homemade devil costume?
https://www.youtube.com/watch?v=csIl72_lAl4
How do you make a Devil pitchfork?
Another idea for making a devil's pitchfork is to cut two pieces of red felt into a pitchfork shape. Use felt glue to seal the edges, leaving the bottom open. Allow the glue to dry and stuff the pitchfork with cotton balls. Paint a gift-wrap tube, broomstick or wooden dowel red and place in the bottom of the pitchfork.