Use a wooden beam in the ceiling to hang your swing on. If there is not a beam, a trip into the attic may be necessary. Once you are in the attic, look for a ceiling joist or rafter to secure your swing.
Measure the distance between the chains and place marks for your pilot holes. Drill your holes with a bit that is smaller than the screws you are using to hang your swing. There will be a hole for each screw.
Screw the lag screw eye bolts into the joist, beam or rafter you marked. Place the swivel hooks onto the bolts. Swivel hooks have a rubber cushion that will make swinging smoother and quieter.
Hang the chains onto the swivel hooks to the length that is comfortable to you. There is usually a front and back chain on each arm off the swing. They join and hang from each swivel bolt. If the back chain is a little longer than the front chain, the swing leans back a little for more comfort.