You learn to breathe into the lower part of your abdomen.

Which, if you smoke or spend time in smoky surroundings will impair your lungs?

Give up smoking and parties.

Relaxing your joints.

Which if you are training by water or cold saturated air can give you arthritis.

Don't train by water or cold saturated air stupid.

Relaxing stomach muscles.

Big belly.

Don't drink so much alcohol.
Do some sit ups and back raises you fat gimp. 
Just because you relax them doesn't mean you stop using them, 
one of the biggest muscle groups used in TCC is in the waist area.

Doing TCC when you’re young.

Friends take the Mickey; think you’re a puff, soft and weird.

Use your time alone constructively. Become bitter and twisted focus on training to become the very stench of evil. Then revenge is sweet and the time behind bars can be used to do more training.
Don't forget your endless pursuit for perfection.

Teaching Tai Chi Chuan.

A tendency to disappear up your own ass hole.
Some of your students will see you as a God and will believe anything
you tell them. I once had a class hopping on one leg for 5 mins for no reason but for my own amusement. I know what you’re thinking? 
I also have had students believe I had the ability to release chi into them and 
as a result would throw themselves on the floor from the mere touch of my hands. I may have released a fart but that's about it, maybe it was the smell.

Keep it real. (Ali G style)

Chi bolts and the like are about as real as Pamela Andersons Breasts.
Oops sorry didn't you know.
Only the gullible and easily lead will fall for this, but it’s a good way of keeping the secrets hidden.
I have trained in the East with quite a few Tai Chi Masters and they just laugh and think its quite funny "to many kung fu movies".
Yes chi means energy and can be used to describe petrol, coal, wind, water, 
electricity and so on.

Bad Tai Chi.

Yes doing Tai Chi wrong can and will knacker you up as well as empting your pocket.