how to pick depth?

Shiny new to crappie fishing. Now that the pre-spawn/spawn is here....how do I pick a depth for catching crappie around tree tops near the bank? I plan on fishing a jig/live bait under a cork. Where do I start? If I just start at a random depth and am not getting bites do I assume there are no fish there...or that I am at the wrong depth???? Thanks for any input!

With no depth finder Put out two ft. and work your way down . Always think shallow when dirty water is present . Pay close attention as to where bites come either on the way down (at what depth . ) with a depth finder start a ft. above depth of most fish on screen . This is what I still do . I am no guru just wanted to give you a starting point .I will watch this thread to learn what others do . Always be open minded it shortens the learning curve . :highfive

I fish all from bank, I don't use minnows but if I were to I would put a jig on one and fish it until I found what depth fish were hitting at and set the bobber on other rod for that and start from there. That would dial me in enough to fine tune after that. At least I think that's what I would try, and I know I would probably lose a few jigs if Im over brush so I would take quite a few with me.