mook jong man
Senior Master
without the total relaxation it is impossible to produce Nim Lik, you can tell from someones form if they have it or not....
and on a side note i never practice in front of a mirror,
That is true , but you have to have structure first.
One has to make sure the movements are correct and learn to relax "within the structure".
Occasionally you should practice in front of the mirror , over time things have a tendency to go out of whack so to speak , wrists will deviate from centre , elbows will flare out etc.
I will echo what Yak Sao said about defining the techniques , pulling your arms back as far as your injury will allow because it is an important stretch for your chest and shoulders.
Also make sure you explore the full range of movement in your Huen Sau , keep the hand flat and rotate your wrist right around , it should almost hurt.
Not only is it important for wrist flexibility and strength it is also crucial for making the Huen Sau work properly against an opponent.
Remember structure and "correctness" of technique first , then relaxation , and finally application of mind force.