Is this a good way to show my best friend what she means to me?

My best friend is amazing. I can talk to her about anything. And she knows me better than anyone. But I feel like she should know more. More about my past. I decided to write a note telling about every big event in my life. All the way up to now explaining what she means to me and how much I love her. But I’m not sure if it’s the best way to tell her… What do you think?