Quick background. I'm now in my late 30s. In my early 30s I had lifted on a starting strength routine. Got my gains, got in a relationship (that eventually failed) and stopped lifting. Yesterday was the 4th week of following strong lifts after about a month previously of stupid fucking around without a real goal or program.

Stupid me thought I'd remember form from my previous experience. Turns out I was wrong and now my left shoulder is in pain when I try to get under the bar for squats. Little to no pain at rest but I don't have full range of motion if I try to scratch the back of my right shoulder. If I try to hold my arms back in a squat position, then that is painful and highly uncomfortable. (Self diagnosis that my elbows were too high and I wasn't flexing my upper back enough with the loaded bar) I thought it was typical started lifting again soreness so I pushed through it until yesterday. I tried getting under the bar and it hurt beyond just hey you're sore. Listened to my body and I'm giving myself a week off from loaded squats (body weight only) to see if that's enough recovery. I'm also re-reading starting strength 3rd edition so I can get my form back on point before the weight gets too heavy and I really hurt myself.

Long story short, I need a basic stretching routine that will help me get the flexibility I need for the big 3. Googling for this kind of routine gives you a stupid wide range of results, so I'd like to narrow that down to an effective program. My intent is to add a stretch routine to my daily rituals.