Mass Tip: Perfecting your form
PERFECT YOUR FORM
The most important part of strength training is learning the guidelines for each move, says David Jack, C.S.C.S. When you're loading your body with weight, you put yourself at risk for injury, especially if you aren't using the correct form. Even if you manage to avoid hurting yourself, the strength-training move won't be as beneficial if you're not doing it correctly. So, to be safe, make sure you can nail the form before you start adding more weight or even any weight at all.
Source; https://www.womenshealthmag.com/fitness/g19918887/top-form/, https://www.womenshealthmag.com/fitness/g19989223/best-ever-strength-training-tips/