To texture ceiling with swirls, you should first clear the room's floor and cover it with plastic drops to prevent the process from messing up things. Secondly, clean the surface of the ceiling and then mix the drywall compound in a bucket. Apply the first coat of the compound and let it sit for 2 hours so that you can apply a second and a third coat. Finally, you can use a knife to make the swirls before the 3rd coat dries. For more information you can refer to http://www.ehow.com/how_7483558_swirl-textured-ceiling.html.
thin drywall mud with about a 5 to 1 ratio with water and using a whisk broom,or as i hve done,a coffee can apply it to the ciling with a swirling motion when it drys very lightly sand it with a sanding pole to knock off long peices....practice first