Emeril's(R) or Tony Chacere's Cajun seasoning blend is best. If you do not like okra you can omit, but must use gumbo file powder in its place.
Add shrimp stock slowly. Gumbo should have a stew-like consistency, do not make it too soupy! If you are using pre-cooked/seasoned shrimp, add and turn the burner off; shrimp will be hot in 10 to 20 minutes.
To manage time, prep all your ingredients while stock is cooking. Do not add any extra Cajun seasoning to gumbo pot until after shrimp are added. Shrimp are already seasoned so you may not need it.
Gumbo tastes even better the next day because the flavors have all had a chance to mingle and settle. But keep in mind the spice will be more prevalent.