I stole this from a disused Gallente board.
Ok This is by no means an "Optimal" Setting, but it will keep you out of trouble for a bit!
Step 1 - Create a New Overview!

... and Choose "DESELECT ALL" ... so we get rid of everything in the overview!

Step 2 - Select everything you want to see
Firstly we want to show all ships!!

.. and we want to see some celstials like jump gates and faction warefare stuff!
Dont add Drones, they will clog the overview, maybe set a new overview tab for just drones.

Step 3 - Select All of The States you want to see! (We don't want to see people in your militia or gang - we want to see all others )

and we can also set colours to make things easier. IF you see something Red on your overview then you can shoot it!!

and make sure you have Ewar on !!

Save these settings as War or FW or I like Pink Ponies
Now you know how to setup your overview you can add or remove things to suit your needs.