Disclaimer: This is speaking from experience in a different job market than Norwegian, but I imagine many aspects *cough* translate across borders.
It's not that you have to have some crazy credentials to do the regular translation jobs. I.e. not sworn translations or translating for the EU, UN etc. Showing a proof of your ability - e.g. a paragraph or two of some random translated text - should be enough for starters. Later on you'll have the working experience as well.
There's a whole lot of unglamorous stuff that has to be done by somebody, often not because anyone strictly needs it, but because the law requires it, or some manager thought it would make their company look good to have bilingual everything.
Like translating operation and maintenance manuals or health and safety notifications, etc. for new products or industrial machinery. Or tender documentation for some construction project that needs to be posted on official boards. Or some correspondence between small businesses.
Oftentimes half of the job is typing the thing and formatting the document (because the original was in PDF or a scan of some old paper pages). Remember that any business that for whatever reason has to translate something has a few choices - either tell one of their employees to do it on their (paid) time, hire a translator on a permanent position, or contract the job to an agency. That's where you come in.
Contact some translation agencies (don't have to be in Norway), tell them you're looking to get your foot in the door in the business. Send them some examples of what you can do (a few paragraphs on different topics) - or they might ask you to translate a short bit of their own. They'll likely put you down on their stable of contacts, because even if you're not that great, sometimes there's just nobody else available and their clients can ask for a job to be done by tomorrow.
Then you just sit on your arse and wait for them to contact you. From then on being reliable and not picky about taking jobs counts for more than having credentials.
(Oh, and being a 'native' Amerrhicun counts for a lot - general preference is for the target language to be a native one)