Follow the yeast link in my signature. I use a sanitized glass to scoop the goop out of the bottom of the fermenter.
EDIT: Oops, just realized you're talking about a carboy, not a bucket. For a glass carboy, flame the mouth of the carboy briefly with a propane torch. For a plastic carboy, squirt some Star San (or equivalent sanitizer) on the carboy mouth and let it sit for the recommended contact time (a couple of minutes). Swirl the carboy around until you get the trub and yeast a bit loose. Pour all the "good stuff" into a sanitized jar or flask. Proceed with the rest of the steps outlined in the yeast link.