If you are a citizen of a non-EU country and want to work in Sweden, you will probably need to obtain a work permit.
There are diffrent type of work permit in Sweden. If you are unsure which work permit you should apply for, visit the Swedish Migration Agency’s application guide.
You must have been offered a job before you can obtain a work permit. You cannot enter Sweden until the permit has been granted. You cannot obtain a work permit to go to Sweden and look for a job. Detailed information regarding rules, regulations and criteria’s to obtain a work permit can be found on the Swedish Migration Agency.
For employment that lasts less than three months, citizens of certain countries must have both a work permit and a visa. Detailed information about visas can be found here.
If you plan to work for a period longer than 3 months to start up or run your own business or become a part owner of a company, you must have a residence permit. You cannot enter Sweden until the permit has been granted. As self-employed you are not allowed to take employment with any employer. You can find more information on rules and regulations on the Swedish Migration Agency's webpage.
The easiest way to apply for a residence permit is to apply online over the internet. An online application goes directly to the Swedish Migration Agency.
If you are still unable or do not want to apply online, you can submit an application at the Swedish Embassy.