Ah well, to condense it further.
Stop bad habit has greater effect than creating good habits at first.
Don't over train.
Deadlift and Romanian Deadlift or Stiff legged deadlift are great for lumbar, glutes, and hamstrings.
As far as habits are concerned:
Get on a regular sleep schedule, 7 hrs total if possible.
Reduce or remove junk food from diet, particularly stuff high in processed ingredients like corn syrup.
Walk more. For most people walking 30mins a day is a massive improvement.