Two ways to easily unmold gelatin: 

1. Spray the mold with cooking oil before filling. If you want to avoid an oily film which might cloud the surface by using oil spray, simply rinse the mold with cold water prior to filling.

2. Dip the mold into warm (not hot) water to the depth of the gelatin for 5 to 10 seconds, loosen edges with a knife or spatula, and unmold. Return to the refrigerator for 20 minutes to refirm.

Tip: To center a mold on a plate, rinse the plate with cold water before unmolding the dessert.