Throwing this out there: A simple approach for BB'ers, because stretching can be very, very boring for most of them. Works for a lot of people. Just a suggest, stretch or don't any way you wish.
Hang from a chinning bar, as you relax the shoulder girdle. Starting with a extra wide to shoulder wide grip, also include a grip close grip (hands touching or near touching..a more natural grip would be a hammer grip...thumbs facing back). Take around 30 seconds, or more, per hold. The secret is relaxing, as in most stretching undertakings. Let gravity do it's thing with this natural method. As you become adjusted to these hangs, some will do them one hand at a time. Some also, including me, will add weight (belt & chain), which appears to help greatly with my lower back and the whole chain of the spine. Almost like a chiropractor adjustment. Has spinal/disk surgery while in college and the back will stiffen up, on occasion. These hangs seem to help quite a bit.
Lower back/hams/calves: Place the toes on a 2X4, BB plate, etc. Clasp the hands together behind the small of the back, keeping the chest high, spine and upper back straight. Bend down, like doing a GoodMorning exercise and hold for 5 to 10 seconds. Come back up and repeat. Do as many reps as you think you need, but always keep the spine/back completely straight throughout the stretch. With the toes raises, you are allowing a fuller stretch to the calves and hams. And should also get a great burn to the areas. Good Luck
Side Bar: I'm aware of the dynmic-static thing. This debate has been going on for quite a number of years. Giving about 6 months, there will be another White paper that will say that the static position is better. Another 6 months a new White paper will say that the dynmic approach is better..and on and on and on. Guess that what college and private grant are for. Grants are the mothers mike of any research and educational institution.