You got a diagnosis that it is herniated?
Keep your back in a neutral position as much as possible. Reduce spinal flexion and extension.
Its possible for it to repair itself, depending on severity, otherwise surgery might be needed if it gets worse.
Spinal bracing movements, static core work, glute work is about all I might suggest. Minimize spinal loading at this point in time.
Check out the work of Gray Cook for info on bracing.
NY Iron might be able to give you more info.