Method 1 This method is good for bamboos that are 1 inch or larger in diameter with over 25 culms, upright stature and tight clumping. It should work no matter how large the bamboos get as long as there's a high enough ladder and enough string. I used this on my phyllostachys aureosulcata(yellow groove). It's almost effortless and could be upgraded with a layer of plastic, but I really doubt YG will leaf burn much anyways.
Here's how it looked before the protection.
Method 2 One way to add to the first method is to add a layer of tarp over the entire clump. This provides more wind protection and even prevents temperatures from reaching quite as low where the foliage is. This is phyllostachys atrovaginata at 13ft tall, and if it was any taller, it would simply need a larger tarp.
Method 3 A method that only takes a few seconds, but works very well with small bamboos is simply laying a heavy object to weigh the plant down such a a large branch, log or brick. It works exceptionally well for an area that gets residual snowfall overwinter such as here in NY as the snow weighs the foliage straight to the ground. I used this on the fargesias.
Method 4 This is probably the most effective method to overwinter bamboos as the culms are bent to the ground and tarped over with some kind of protective cover such as plastic. I've don it on most of my bamboos and it will work as long as the bamboo is flexible enough to bend to the ground without breaking. Some species of bamboo at maturity will maintain their flexibility. I used this method on many of my bamboos.
Phyllostachys edulis moso bicolor
Phyllostachys dulcis This one also required a stake tying the culms to the ground as the tarp alone couldn't hold it to the ground as 1 inch culms were harder to bend.
Phyllostachys propinqua beijing This one also needed a tie down stake.
When a bamboo is simply too big, I sometimes need to use a combination of methods such as with my phyllostachys parvifolia.
Overview of bamboo garden after protection
With some of my other plants I will simply put a leaf bag over them or cover them up with fallen tree leaves to get them through the winter safely.