Two important skills to learn for good Tai Chi.
Find your opponent’s center – disguise your center
Practice push hands blindfolded – increases sensitivity – decreases anticipating partners moves
Be aware of Yin & Yang in your form – e.g. Left leg forward: Left leg & right arm are Yang – Right leg and left arm are Yin.
When extending your arms – don’t lock your elbow joints – leave some Yin there (slightly bent).