Just about the same as everyone here really, Azura started out as a random creation of mine, and then I kinda switched her markings up to give her a bit of a more human look. And the others...yeah just random creations. xD
It really just came to me one day. I got really excited it was something I could easily imagine and have look good at the same time.
I did have one big inspiration for Green though, which was LupisVulpes' (https://www.youtube.com/channel/UCFtM8Vl0VwKeEMSCdJ5EjAQ) character Sad Blue. Sad Blue mainly inspired her main color, which happened to be blue. My main issue with making a fursona was the main color and apparently looking at Sad Blue really helped. I then gave her a very fuzzy black jacket and light red eyes (It wasn't even intentional that red and blue make my favorite color), changed the shade of blue, and yeah that's how Green was born. There was no plan involved in any way possible.