What type of supports do you have in place so you do not backslide into that dark mental place again?
Do you have a pdoc?
Take medication?
Have a psychologist?
Have a social network?
You need a plan that incorporates good hygienic lifestyle routines, as well as supports and a way to monitor yourself so you can reach out for help if things start to get bad for you.... you need to also have a crisis plan.
You can google "putting together a mental health crisis plan" for ideas on how to put one together, or "mental health crisis checklist".