If you are casting a part in an open or one-piece mold, pour slowly from one corner of the mold and let the material flow naturally to fill the mold. If it is possible to run the material down one side of the mold. If the mold has an undercut or complex corner you may pour the material to that point and then rotate your mold to evenly coat that area before topping off the mold. If you are pouring a closed or two-piece mold, fill it completely until the material comes out of the vent hole and then tap the mold on the table to release any bubbles that may need a little assistance to get through the vent hole. You may also wish to rotate the mold and possibly squeeze the sides of the mold to assist hesitant bubbles in reaching the vent.