I know certain movement can actually do more harm than good, so how do I know if I have the proper posture for a stretch?

I learned from an orthopedist that every movement is good for your body. I always look at it this way: do I still feel good inside while doing it? Does this pain feel goods for me. Your body can answer all the questions if you let it. 😊

When you are stretching, aim fore the slight pain in your muscles. Feel them pull and contract. If what you feel is a sore or sharp pain, than you are probably doing some things wrong.

Try to do it in front a mirror and before you start watch the poses so you can have an idea what it’s coming next but most important while you are doing pay attention to your breathing and listen to your body.

Try to listen to your body's cues. And try not to focus on how far the stretch goes but let your body naturally fall deeper as your proceed over time.