Hi there,
There are no hard and fast rules when it comes to the frequency of bathing dogs. Its just like with us - someone with long hair will probably wash their hair more frequently than someone with short hair, it comes down to personal preference.
So, I wouldn't worry too much about having a strict regime as to how often to bathe your dog, just give them a wash when you think they need it
Once a week or once every 2 weeks should be fine, but don't worry if your pup gets dirty and needs more frequent bathing.
Most importantly use a product designed for animals, rinse well and make sure you dry them well afterwards.
Hope this helps
Kate