I haven't done one in a while, but I think you resurface the ball first and apply wax to it.  You then put it in the chamber (I put it in holes down so they didn't fill as much).  You fill the chamber until the ball is completely covered.  I used a mask when doing this because the "fumes" of the sand gave me a tickle in my throat even though I really made a conscience effort not to inhale.  I left it in over night and vacuumed it off the next day.  You can then take it to whatever grit you want (I think Ebonite mentioned polishing before hand was an important part of the process to break off fragments on the surface).  They idea of it all is to draw the plastcizer that is blocking pores out of the ball.

I did an AMF Valor with amazing results and other balls not so much.  Mo Pinel told me at a seminar that Hook Again works for the plasticizers in Ebonite balls and may not be required for other companies balls.  Brunswicks plasticizers seem to come out from heating, deep cleaning, and scuffing.  Giving your equipment this much attention is only going to yield positive results even if you can't get them back to "like new" status.  I hope this helps.  Good Luck.
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Where is the bait?  I'm goin' to jail!!! - Chocolate GAYzer