Posture Correction Shoulder Harnesses and Tape
I used to recommend some fairly intricate kinesio taping to help with posture modification for my clients but I have found that a simple posture correcting harness/brace does a fantastic job and are much easier to use. You do not need too heavy duty of a harness unless you have extra thick shoulder musculature, are looking for a more aggressive correction or are very active throughout the day. The nice thing is that you can try as many different posture correctors from Amazon as you want until you get the right fit and just return the ones that do not work for you.
I do not use the harness for “mechanical” support or cinch it up tight. I put it on a little loose so that when I start to lose my posture I feel it pull on my shoulders which provides a nervous system stimulus and then I correct my posture in response. This trains my nervous system to create a self-correction loop that I hope will become automatic over time.
I have even put little thumbtacks in the front of the harness so when I start to slump forward I get a little more nuanced nervous system nudge to find a better posture. You can do a similar thing with K-Tape by making sure the vertical tape is as tight as possible and goes as high up on your neck as is workable for you.