You know, a trap would likely be the best/easiest way to catch common yearly ones.
I think it would be easy when they are swarming though, just get a 5gallon bucket, and scrape some off a wall
The best way to "trap" them that I can think of, would be to get some mesh netting, and make a "tent" all the way around the base of a tree. About 3' up, and about 3' out from the tree. Like a cone see? Do that to a bunch of trees, and check them in the evening and morning.
The one in the video that I fed off, I found while going to check on my chams one night. It was wiggling around on the ground, trying to free itself. I assume it had fell off of a nearby tree. It wouldnt have been able to properly extend its wings without hanging anyway, so I snagged it, and watched it do its thing. It happened so fast, I missed a good deal of it, but it was interesting:
This one, landed upside down in some tall grass right beside me one day:
Ive also caught them after they have ran into walls and such at high speeds, they get stunned for a bit, and are easily caught.
Send enough time outside where they are found, and youll get close enough to snag one.