Weigh 50 grams of dried ginkgo leaves using accurate kitchen scales and place them in a blender.
Measure 400 ml of 100-proof vodka using a measuring cup and place it in the blender with the dried gingko leaves. Blend until well combined and the leaves are small particles.
Pour the blended leaves and vodka into a sterilized large-mouthed jar and close tightly. Leave in a cool, dark place for a minimum of two weeks and up to six weeks, shaking the jar daily.
Line a colander with cheesecloth and place both on top of a bowl. Strain the gingko leaves through the cheesecloth, removing as much liquid as possible. Strain the liquid once more through a coffee filter to ensure all the leaf particles are removed.
Fill an amber glass jar, or several glass dropper jars, with the processed ginkgo leaves, and label the jars with the name and date the extraction was made, as well as that it is a one-to-eight ratio extraction.