http://www.nationaldayofslayer.org sez :
# Stage a “Slay-out.” Don’t go to work. Listen to Slayer.
# Have a huge block party that clogs up a street in your neighborhood. Blast Slayer albums all evening. Get police cruisers and helicopters on the scene. Finish with a full-scale riot.
# Spray paint Slayer logos on churches, synagogues, or cemeteries.
# Play Slayer covers with your own band (since 99% of your riffs are stolen from Slayer anyway).
# Kill the neighbor’s dog and blame it on Slayer.
Also a fun day to play with your Slayer Barbie ( thanks ektopia ), or listen to commodore 64 & NES renditions of Angel of Death. The Japanese accapella artist Dokaka’s version is pretty great too.
Buy your fake blood early.