One or 2 good diskings. If you do more than one, run at different angles to each pass. Don't follow the planter rows, go at an angle across the field. Instead of due south, go 15 degrees off of south.
Do not disk too much. _That_ creats a very hardpan zone about 4-5 inches deep. You don't notice it, but those disk blades will stop the same depth all the time, and pack the ground very hard.
Then go over the field a time or 2 with a harrow, aka drag. Some will use a pole or rr tie or I beam or chainlink fence or bedspring. A real drag will be better, the other stuff works if you have time.
Again, the most important thing is to drag the field at different angles. 45 degree ange or so, head to the south-west, if you drag it a second time drive to the south-east.
Going at different angles is the key to getting a field level. The disk will loosen a few inches of dirt.
The harrow will move the loose stuff into the low spots, but will do much better at it if you are going in slightly different direction to whatever direction you were going the last path.
A packer is wonderful for going over the field after you seed it. The packer distributes it's weight over all the ground, and makes a firm seedbed in the top inch, which is exactly what grass & legume type small seeds want. It is not good for leveling the ground, nor will it compact the soil. It just makes a perfect seedbed once the seed is on the ground.
--->Paul