Wait until after dark, then grab him off the roost. He may freak out at first, but most chickens settle down fairly soon if you hold them securely but gently, and maybe talk softly to them.
Then carry him somewhere with light, or have a headlamp on in the first place, and you can do wing-trimming or anything else you need to do.
Or to catch a chicken in the daytime, slowly shoo it into an enclosed space (fenced run with a roof, or coop, or something like that), then go in with the chicken and shut the door, then corner the chicken and grab it. Again, it will probably freak out briefly, but most chickens settle down fairly soon.