If you plan on relubing your cube with anything, I would really suggest to take it entirely apart and wipe down everything with a papertowel or cloth (as long as it doesn't leave fuzzies)
Reapply the lube that you decide on using, if its non aerosol I would follow the Lubix Tutorial at :
http://youtu.be/UXQ-VGhsUKw
This is slightly outdated as we have improved the lubing method.
When lubing the core, pull apart the center caps to expose the screw and apply a fat bb size of lube, while still holding it apart, spin the core with your fingers to work the lube around the screw, slowly allow the center to come back together then move on to the opposite side, repeat till all 6 are done. Plus you will have a green dispensing tip (If you buy Lubix that is)