Sorry to have to tell you this but you're just going to have to get used to it as long as you own a GSD. It would be an understatement to say that German Shepherd's shed.
German Shepherd's DO shed... A LOT. And twice a year, you can expect your German Shepherd to "blow" their coat - even more hair all over your house - and if you had a female you could expect even more hair, especially during the molting season.
Just expect to sweep or vacuum several times a week - especially during the time these dogs "blow" their coats. That's just what you have to expect and this from someone who's lived with one of more of these dogs indoors for over 30 years.
Daily or weekly brushings of your German Shepherd outside will substantially cut down on its shedding overall and also the amount of dog hair found throughout your house. But other than that, taking care of all that hair and doing a lot of sweeping is just part of owning the breed.