Deer have horrible vision - 20/100! They have a 360 degree view horizontally, but they cannot gauge what is directly in front of them, or over their heads after 7' feet high. If gardeners don't let deer know that a fence enclosure is ahead, deer may run right into it (especially if they are being chased by a predatory animal like a coyote or wolf).
Because deer vision is so poor, Deerbusters recommends adding white warning banners to the deer fence to let white-tailed deer know that a structure is near. Whitetails have trouble seeing the black color of the fence mesh; but they can easily detect the white color on the deer warning banners. We recommend that you tie one white warning banner on the fence for every 10 feet in the middle of your fence line. Avoid adding warning banners to the top of the fence -this allows the deer to gauge how high they need to jump to get to your garden.
Just measure and cut!