Abstract: A sign sleeve includes a hollow cylinder that conformingly fits around a crossbar. Two opposing side flaps can be opened for draping the cylinder over the crossbar and thereafter fastened to close the cylinder. An exposed face of the cylinder bears sign indicia. Preferably the cylinder is formed from a rectangular planar sheet defining creases for folding the sheet into the cylinder. An implement on a pole temporarily interlocks with a sleeve to carry the sleeve up to a remote overhead crossbar and drape it over the crossbar. Preferably the implement further includes a framework for guiding the flaps into a closure disposition and for forcing closure. A method of posting a sign sleeve on a remote overhead crossbar is also disclosed.