osnivanje preduzetnika

1. registration of a sole proprietorship; setting up as a sole trader
   Na sajtu APR-a izaberite opciju osnivanje preduzetnika. — On the APR website, choose the option for registering a sole proprietorship.
   Popunio sam registracionu prijavu za osnivanje preduzetnika. — I filled in the registration application to set up as a sole trader.

Literally "founding an entrepreneur": it means registering the business; in speech people more often say otvoriti radnju / firmu.