Stretch the curtain wire across the width of the ceiling or window. Cut the wire to a length that is 6 inches longer than the width across the ceiling or window.
Use a level to make two evenly spaced dots with a pencil on the ceiling, one dot on each end. The dots will be where you place the hooks to hang the wire. If you are stretching the wire across a wide distance, such as the entire width of the wall, make a third dot halfway between the two end dots.
Drill a hole at each dot. Each hole needs to be slightly smaller than the thickness of the anchors you are using.
Push anchors that are appropriate for the type of ceiling you have into the holes until they are flush with the ceiling.
Screw hooks into the wall by hand until they are tight.
Fold each end of the wire into a 1/2 inch loop. Secure the loop with 1/8 inch wire rope clips.
Hook the loop end of the turnbuckles onto the hooks on the ceiling. Then hook the looped end of the wire onto the hook end of the first turnbuckle.
Stretch the wire across the width of the ceiling. If you have a hook in the center, place the wire on top of the hook for extra support. Hook the loop of the end of the wire into the hook on the turnbuckle.
Tighten the screws on the turnbuckles so that the wire is pulled tightly across the ceiling.
Attach the curtain clips or hooks to the wire and then hang the curtains from the clips.