I know it's difficult for some people to type themselves in association with the functions but I hope that my small guide will help you.
It maybe hard for you to look at these 8 functions and say "which one do I use?" "which one do I use first?" "which one do others see me using?" but I feel as though the best self discovery may be made through journaling. Some topics you should explore are:
1. Ask a parent and a sibling "what am I like?"
I know when I ask my cousins they often tell me "you're very calm" and "you sit in the corner and journal even when you're at a party" so I journaled this and later on it meant that I don't do much Fe. So much of this meant that I was an introvert. Anyway, you get some interesting insights and objective perspective about yourself when you ask those who know you well.
2. You should write down what you say, how you react, what you react to. Your words are often very important in exploring the functions. If you happen to want to draw attention to yourself in a theatrical way, or you feel left out and need to feel important or included by others...these all shed interesting lights about you.
Long story short...journaling is a wonderful self discover and I encourage it.