Give your Shih Tzu a thorough brushing at least once a day.

You will notice the difference in several areas:

1. The coat stays cleaner for longer periods of time.
2. Your Shih Tzu starts feeling closer to you (and starts accepting you more as leader not as its slave like most Shih Tzu will have you believe).
3. Circulation improves.
4. Grooming sessions become easier over time
5. And most important, you become more aware of your dog's overall health.

I cannot tell you how many times I have spotted health problems just before they become troublesome, just by brushing my dogs daily.

So the difference will be noticeable if you can get yourself to do it every day.