Simple -- list your three favorite superheroes, and three favorite supervillains. (Feel free to list runner-ups, if you wish.)
Mine:
Heroes
1. Spider-Man
2. The Flash I (Barry Allen)
3. Animal Man
Runner-ups: Superman, Flash II (Wally West), Silver Surfer, Daredevil, Green Lantern I (Hal Jordan), Nightcrawler.
Villains
1. Green Goblin I
2. Magneto
3. Joker
Runner-ups: Lex Luthor, Galactus, Zoom I & II, Captain Cold, Doctor Octopus, Juggernaut.
Mine:
Heroes
1. Spider-Man
2. The Flash I (Barry Allen)
3. Animal Man
Runner-ups: Superman, Flash II (Wally West), Silver Surfer, Daredevil, Green Lantern I (Hal Jordan), Nightcrawler.
Villains
1. Green Goblin I
2. Magneto
3. Joker
Runner-ups: Lex Luthor, Galactus, Zoom I & II, Captain Cold, Doctor Octopus, Juggernaut.