Here's a list of the top 5 ways to squirrel proof your bird feeder:
1. Install your bird feeder in a way thats very sturdy and doesn't swivel, swing, or turn easily.
Why? Because squirrels can be very aggressive and very often figure out that they can "shake" the feeder easily to get the bird seed to drop down on the ground where its easy-to-eat.... every single day... and its super-annoying.
2. Setup your feeder where the bottom of the feeder is at LEAST 5 feet from the ground. Higher is typically better.
Why? Squirrels can jump crazy high, and as such, they can easily jump onto your feeder (thereby also shaking/swinging it violently), grab on, and eat up your poor birdy's food.
3. Locate your feeder in an area that is > 5 feet from any fences, poles, short roofs, tree trunks & branches, etc.
Why? Because squirrels can easily climb up these type structures and... again.. use them to jump onto your feeder, shake/swing, & eat up all your birdy's food.
Why? Squirrels HATE this smell... Hate it. They stay away from anything with this repellent scent.
5. Buy a highly-rated bird feeder that is SPECIFICALLY designed to be "squirrel proof".
Why? Because "regular" bird feeders that you'd typically find in your local nursery or big-box store are typically 100%, absolutely, completely, & ridiculously NOT designed to protect your birdy's food against those little terrorist squirrels.