There is no scientific or absolute recipe for making your own topical green tea extract product, so use caution. Adjust your recipe as you learn what works best for your skin.
One recipe suggests using two tablespoons full of green tea added to ¾ cup of very hot, but not boiling, water. Steep the tea for five minutes, then strain it through a fine filter or cheesecloth. The remaining liquid should equal about ½ cup of strong tea. Let the liquid cool completely, maybe overnight. Select your base cream. Basic emollient creams that do not contain any added preservatives or fragrances are available for purchase and are not expensive. Use a sturdy spatula, or even a blender or electric mixer, and add cream to the tea in small portions until you have the desired thickness. Store your cream in a jar or other suitable container in a cool, dry place. Remember, you did not add preservatives. Do not keep your cream around for an extended amount of time. Store your cream in the refrigerator, but not the freezer, to extend the time it will remain uncontaminated.