There is only one way to ensure or guarantee the best time and place to get a prize or monster fish...At the local fish market and as for time...when they are open for business
What is your location? Someone might have some local knowledge about fishing spots.
Some fish do have "best baits". But quite often it depends on what the fish are eating at that time. I call it match the hatch. Match your bait or lure to what the fish are eating, which in some cases can vary from one day to the next.
If you use the above search box and search the word "catfish", you will find more than 250 topics talking about catfishing.
Good luck. Let us know how you go
itsaboat mate...Life is just a boat and then ya marry one !
What I have used for catching large numbers is whole anchovies to the point where I would put 50 in the boat when others using shad would catch 6. For large flatheads - they will only hit live bait. Use 1/4" pieces of a Sim Jim on a hook leaving the point exposed & catch bait. Using a circle catfish hook set the hook under the dorsal fin (top fin along the back) & with scissors cut off the bottom of the tail fin so the bait will swim erratically. I will set out 1/2 dozen baited like this using tubes & milk jugs 30lb test line & have caught large cats to 55lbs allowing them to tire themselves out pulling the jug & tube. Having a gaff hook in the boat with you is a must.
Edited - Best time to catfish is at night & moon phases like full & new.