From 2011.igem.org

General Digestion Protocol

10 uL DNA

5uL buffer (check http://www.neb.com/nebecomm/EnzymeFinderSearchByName.asp for a list of enzymes and associated buffers)

0.5 uL BSA (if required. See above)

1uL enzyme 1

water to 50 uL (32.5 uL, add first)

If two enzymes are required, check http://www.neb.com/nebecomm/DoubleDigestCalculator.asp for buffer, temperature, BSA specifications.