Create your own, ideal dracaena planting mix by combining equal parts of potting soil and vermiculite. Mix the two together well, fill the pot halfway with it and water it well.
Slip the dracaena from its pot. If it's pot-bound – with the roots circling the pot – it should slide out easily.
Use your fingers to tease some of the outside roots from the rootball. Loosen the fatter roots and cut off any that look soft or damaged. Place the roots into the new pot and check its depth. You want the plant to sit at the same depth it did in the old pot, so add more soil if necessary.
Fill the pot with the soil mixture to within 1 inch of the rim. Water the dracaena until water runs from the bottom of the pot. Allow it to drain for 15 minutes, then water again. If the soil settles, add more so that the surface is within 1 inch of the pot's rim.