Every few days or so you should brush the dogs hair to help with shedding.
If you brush the dog every few days you keep the dog from leaving fur on things such as furniture, blankets clothes etc.
Then if you want to take the dog to a professional groomer you should do so at least every 6 months to once per year.
My dog gets groomed at home such as bathed, brushed.
I brush the dog every few days and then bathe the dog once per month unless the dog gets dirty and needs a bath.
Then every 6 months I take the dog into a professional dog groomer to have the dog professionally groomed.
You can do it more often if you want too but I can only afford a professional dog groomer every 6 months which is okay.