Congratulations!
One option after you've come out is to do what I did, and keep your existing Facebook profile, and just correct your name and gender and Facebook alias and linked email address. I found the process deeply satisfying. All references to your old name and gender wherever it is linked, automatically update all at once. Its a great way of getting the message out, and it feels great to suddenly be yourself in a thousand places at once.
I kept my history including photos and posts, but Facebook allows you to easily remove photos from your own wall, remove tags from photos elsewhere that you no longer want associated with you, and remove or hide status updates etc from your timeline. There is no reason to delete your account unless you want to, or you have two accounts. After all, I didn't delete me, I just updated my presentation to match my reality. My online identities went through the transition with me.

Oddly enough, I didn't lose a single one of my religious or conservative friends, but ended up gaining dozens of friends who seemed to come out of the woodwork to find me once I was happily me, including many who I hadn't talked to in 20 years! A few expressed gratitude that I kept a few of my old photos with my new name and gender, so they could realize that I was their friend they once new and missed all these years.