Simon,
What I do is make a hose with a beer QD on one end and a a Bronco Faucet (Prt No. BRONCOF&H) you can get from for $7.95 (note no connection to Craftbrewer) Craftbrewer then push a piece of hose on the spout of the faucet make it long enough to reach the bottom of the bottles.
As was previously said lower the gas pressure in the keg, have the bottles chilled and fill the bottle the small amount of head pushes out the O2 and as the hose is in the bottom of the bottle you are not pouring through O2, then cap on the foam.
I can post a pick of mine if needed.
Phil