Assuming it is primarily muscular and not a disc, several things helped me.
Not lifting anything over ten pounds
Not wearing heels
Not doing the cleaning or laundry for several weeks of ot involved any sort of lifting, bending, or twisting.
Being sure not to twist my back as I stand up. So getting out of a bed or car I move both legs and body to the side of the bed or out of the car slowly and then stand. Most people get out sort of one leg and then the other follows.
Some stretching exercises, but nothing extreme.
Still walked around and got some simple exercise. I worked retail at the time so I limited how much time I was standing, but it was still 4–6 hours a day. I don’t recmmend that much, I think I would have heeled faster if it had been less.
You can also take ibuprofen to try and reduce the muscle tension. I would say at least 600mg, just remmebr to take with food and plenty of water. I didn’t take a lot of meds, but if I had. Itially possibly it would have helped me heal faster I think.
My biggest improvement, and when I finally got all better was when my MIL was doing all household chores for me for weeks. Thank God for her. I had been in agony on and off for months, and finally I got better, and have never had it again in over 17 years. Once in a while I get a twinge in my back for a few days, but never the pain I suffered then, and it is never lasting for more than a day or two.
I went to physical therapy and I don’t know if it helped a lot. I went when the injury was pretty new and I was still in a lot of pain. It’s worth a try though. They will help teach some exercises and put the pads on that feel like ants crawling across the area, which a lot of people find very helpful.