1. Screw in some eye hooks on the back of your plywood pieces. Although they lean up against the house nicely (due to your measuring and pre-planning) you can't account for nature/wind. You'll want to secure the presidents to the house somehow to avoid toppling. We used ordinary twine. On our house, George is gently tied to the shutter and Tom is hooked on a nail. The Virginia banner hangs over the door just like a regular hanging sign.
2. Add a spotlight in front of the house on an automatic timer. Unfortunately we ourselves didn't get around to this step this year, but that's OK since George and Tom are used to not having electricity. Next year when we move on to the Roosevelts we'll need to upgrade.