Bay leaves
Thyme
Okra
Garlic
Flour
Bacon grease (if you have it)
An onion
A bell pepper (preferably green)
Andouille sausage
Beef broth
Chili peppers (dried, cajun style)
Tomato sauce (for base)
Crab meat
Sausage
Shrimp
Roux
Anchovies
 
Mix the bacon grease (or whatever oil you've got) with around a cup of flour and brown it over medium heat
Mix your sauce or it's gonna burn
Mince your veggies and add them to the roux
Cut up your sausage as small as you like and add them
Mix that around for a while (your discretion is key in this sort of thing)
Add a few cups of beef broth to a pot and pour in the roux
Mince (or puree) your chilis and add them
Add sugar, salt, olda bay, and your tomato base (I prefer newmans, but it's generally best if you always have some
 
leftover red sauce in your fridge so you can always keep dishes going)
Get anchovies, cut their heads and tails off, and puree them
Add minced garlic to the puree
Add that to the gumbo and stir
Simmer for about an hour at low heat
Fry your okra
Add a little vinegar
Toss in the okra with some crab meat, shrimps, and wocestershire
And bam
Gumbo