you meditate and ask what your element is. there are a number of ways but the point is what one do you feel most connected to your zodiac sign has certain elements attached to them but meditation is the best way to find your element meditate and clear your mind and then ask what your element is. and clear your mind what element comes to mind first would be a good indication of what element yours is.
I suggest meditation because it is yours to find not for me to tell you what element do you feel most connected to? what element are you most comfortable with. really think hard and it will come to you in time