Malazan Empire: starting to write - Malazan Empire

Well first of all, hello. newbie here.

I was wondering, for anyone out there, how long did you plan before you began writing? What kinds of things are the first things that you have built into your world? Did you start with a certain plot, or with certain characters? When do you decide to start writing? For example, I could go for a long time just reworking what's going to happen, but never actually getting around to writing it out.

As for writing, do you plan out everything before-hand, or just follow a rough idea of where things are supposed to end up?

I'm sure this has been asked before, so sorry, but theres too many posts to go through them all to check.