You don’t have to use these specific measurements, if you are wanting to make a bigger drink just to half & half of the liquors.
Mix all together. What I like to do to make it super good is to make a pitcher of these, stick it in the freezer so its SO cold, but not frozen. Then you can do shot after shots with your friends. This drink is so much better when its super cold. Don’t add ice to do it, because it gets watered down so fast.