Place the mold in a bowl containing cracked ice; the jelly will then quickly harden, and the process of fancy molding not be tedious. Have the mold perfectly even, so the jelly will stand firm and straight when unmolded; also, do not move the mold while filling, as jarring or shaking is likely to separate the layers and cause them to fall apart. Have the jelly mixture cold, but not ready to set, or it will take in bubbles of air and cloud the jelly. Pour in one layer at a time and let it harden before adding the next. Do not, however, let it become too firm or gather moisture, or it will not unite, and also will be clouded.