Step 2: Clean bearings and cups
If the bearings are in a cage, and you have additional ball bearings of the same gauge to make it a "loose ball" bearing, discard the cage and clean them all by soaking a portion of the rag in solvent and "shuffling" them in the rag by creating a pocket with your hand and rubbing the bearings into the rag.
By now, you should have a clean-looking set of parts. I hope that you have salvaged an old hub to make this a "loose-ball" bearing kit, but if not, be very sure to use the hem of the rag to clean out the cage. Remove balls from the cage by pressing them inward to push them out. Again, this is not clean yet, and if you plan to re-use the cage, you will have to follow additional steps.