CrossFit is all about health and longevity. You should feel better, move better and look better. With proper form you should be able to CrossFit for the rest of your life.
Here are some general rules that will keep you in one piece and moving towards your goals.
When squatting, make sure your knees are in line with your toes. When standing be sure to push your knees out. Do not let them cave in. Stay on your heels.
Always work to keep your chest up and shoulders back while squeezing your butt & abs. Apply the neutral spine to all movements including rowing and GHD, not just weightlifting and squats.
Keep the bar stacked over your shoulders, hips and ankles by rotating back into the socket. The shoulder is most stable when it is back and down in the socket. A good indicator is when the armpit is facing forward not down towards the floor.
By applying these basic techniques to all movements, you’ll be the best and healthy you for a long time. It’s better to go slow and practice perfect form and range of motion than to go fast with improper form. Nothing is gained from poor technique except greater risk of injury.