I give my male pure bred shih tzu a bath every 2 weeks.
A bath for your shih tzu every 2 weeks should do.
You should bathe your puppy/dog 4~8 times a month.
An appropriate age to start giving a puppy a bath would be around 1 month but if needed you can give a puppy a bath earlier then that but be very careful not to get water in the ears or eyes.
you should probably bath you puppy at 2month es old best
a puppy can take a bath when it starts walking and eating on its own so about 1 month old
Unless he is extremely dirty, a 3 month old puppy should not be bathed yet at all. If you do give him a bath, protect his eyes and ears and be sure to dry him well so he does not get a chill.
If you wanna...
About a month
you should atleast give them a bath 1 or 2 times a month
I think when you get a dog at first you should let it get use to your enviroment. At 6 months I think it's pretty grown. I would probrably give my puppy a bath.
any time is good for a bath i would say atleast once a month