Sugar shake method
(Prof. Sammy Ramsey, University of Colorado)

1. Take 300 bees (3/4 cup) from the brood frames, ensuring that the queen is not included
2. Add 2 tablespoonfuls of icing sugar
3. Roll gently for 1 minute
4. Allow to settle for 5 minutes
5. Invert the jar and shake vigorously to dislodge the mites
6. Add one further tablespoonful of icing sugar and repeat steps 3-5
7. Dissolve the sugar with some water leaving the mites floating

For further information see the Honey Bee Health Coalition.