Here is how I did it (and I apologize for the less than professional graphics).
Find a tree where the squirrels will hang around (pun intended).
Next, lean a branch up against the tree.
We used just a smooth, thin craft wire, but just about anything should work.
Take the wire, first wrap it at least twice around the branch and tie in off. Continue up and over, making a loop that will hang over the top of the branch, just large enough for the squirrel's head to fit through and then loop then end back around the wire, making a slip knot.
Put 3-4 or more of these along the pole.
The squirrels will come to investigate and hopefully end up hanging themselves.
Bonus points to anyone who can identify what type of tree this is.