Discharge all capacitors before soldering by touching the free ends of an insulated piece of hookup wire to both leads of a capacitor at the same time.
Determine the polarity of the capacitors before soldering. In a parallel circuit the positive and negative ends must not touch or a short circuit will result.
Solder 4-inch lengths of hookup wire between the positive leads in a chain of capacitors whose additive value equals the final voltage value desired. Solder 4-inch lengths of hookup wire between the negative leads of the chain of capacitors.
Solder a final positive and negative lead using two 4-inch lengths of hookup wire soldered to the positive and negative leads respectively of the last capacitor in the chain. You should now have a chain of parallel connected capacitors with two end leads to connect to a charging source. The capacitor chain is ready to charge for use.