This is what Wyeast posts on their site:
Sanitize the opening of the carboy.
Pour the water from one of the quart jars into the carboy. Swirl to agitate the yeast, hop residual, and trub from the bottom.
Pour carboy contents back into the empty jar and replace the cover.
Agitate the jar to allow separation of the components. Continue to agitate periodically until obvious separation is noticeable.
While the viable yeast remains in suspension, pour off this portion, into the second jar, being careful to leave as much of the hops and trub behind as possible.
Agitate the second container to again get as much separation of yeast from particulate as possible. Allow contents to rest, then pour off any excess water from the surface.
Pour off yeast fraction, which suspends above the particulate into the third container. Store this container up to 1 month refrigerated. Pour off liquid and add wort, 2 days before brewing or repitch into a new brew straight away.