Stretching everyday will make a huge difference. I've had similar constant, daily soreness in my left shoulder and back, and I've found doing 5-10 minutes of stretching everyday in the morning has alleviated my shoulder and back pain almost completely.
My advice would be to just try a bunch of different stretches and see for yourself - when you find the right stretches that hit your sore muscles you will know right away. Remember them and add them to your routine!
I made up my own personal routine using exercises from the below two videos. I do each stretch for about 15 seconds, sometimes I do a couple rounds of a particular stretch if I'm feeling extra sore that day.
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Video 1:
https://www.youtube.com/watch?v=9jAyRP0bqKAVideo 2:
https://www.youtube.com/watch?v=P8DOZRtIIEQsky touch (just reach to the sky)
toe touch (Video 1 - 5:27)
side pointer (Video 1 - 3:11)
double back hand (Video 1 - 1:45)
cobra to child (Video 2 - 0:43)
pilates saw (Video 2 - 5:48)
straight pilates saw (just reach out straight ahead)
toe touch swoop (Video 2 - 7:27)
butterfly (Video 2 - 9:14)
windmill (Video 2 - 11:55)
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