How to make new candles from old candles?

I really enjoy your column. 
 
My question is: I am trying to clean out cabinets & I have a large box of candles & still more to clean out, some new & some partly burnt.  Some I would like to melt down & remake them but don’t know how.  Can you help me with that information? The rest, what can I do with them?  I really need the room.
 
Thank you,