"lizard" also has another connotation as in 'lounge kizard'. The Soft Parade got called lounge music, the kind that was deemed mainstream compared to earlier work. This assessment was actually incorrect. The Soft Parade was still classic Doors, just where they were arguably adopting a persona.

Save the Everglades.
Sally Ride just took over NASA!
Ha ha!

Well, off the top of my head:

1. Be a musical genius.
2. Good looks dont' hurt, either.
3. Get a recording contract.
4. Get some decent sidemen as band-mates.
5. Get booked on a well-known TV show, then
   promise not to sing 'higher', then renege
   on that promise during the live broadcast.
6. Expose oneself on stage, preferably in Florida.
7. Grow a beard, as one's fame grows, but still
   be recognized by just about everyone.
8. Die young, and be buried in Paris.
   Hey, it worked for him! lol

Theresb68 rumors that "The Lizard King" was his occult name.
He also once said he viewed the universe as a giant lizard.
So maybe he was calling himself God with that name.