If you already have squirrels raiding your bird feeders your well on you're way to easily creating an iconic squirrel portrait. The three basic ingredients needed are. A feeder, a branch, some wood screws and a battery powered screw driver or drill. Most important some sort of blind or hide. Photographing from behind a dark blanket or sheet from a window in your house will work just as well if you don't have a photoblind or other makeshift hide.
The first step is to find a suitable section of branch to photograph your squirrel on. I found a piece of branch that had been broken off by the wind outside of my church one morning. Look for an interesting piece that is one to three feet long with an interesting grain or bark pattern or moss on it. It should be one and a half to three inches in diameter. This will be big enough to hide your makeshift feeders on the back side of it. If you live in the city check with the surrounding neighbors or tree trimmers working in your area for possible pieces of branches.
The second step is to screw the branch onto a piece of scrap wood. Most any piece will do just as it is big enough to support your piece of branch.
The third step is to screw some makeshift feeders onto the back side of the branch. This may take a few tries to figure out how to keep them out of sight. You can use bottle caps or in my case I used a few salsa containers from my lunch at a mexican restaurant one day. Just use anything small that can be attached to the backside of the branch out of sight.
The fourth thing to do is to attach the whole set up to your bird feeder. I have a platform feeder so I just grabbed a few more wood screws and attached it to the side of my feeder. Other possibilities are to clamp it with a "C" clamp. Tie it on with rope or wire. Be creative and figure out a way to attach it to your bird feeder.
The last and final step is to put peanuts or black sunflower seeds into the little feeders and wait. I place my feeder about six to eight feet away from my photo blind with dark trees as a background. I like a dark background so that my subject stands out. What kind of background do you have? A fence or a hedge can work well. Some background that is darker than your subject and is far enough away to be out of focus is a big help.
Now begins the waiting game. Prefocus your camera on the branch and wait. Check to make sure that no parts of the feeders are showing. Maybe photograph the birds that are feeding on your new feeder as well. Don't make a lot of movement or noise and your patience will be rewarded.
Good luck and God bless,