For me an asian here's what I have done
-First fill up a work permit form from labor office (you can go to the office or from the web) fill it up in arabic and complete all the requirements listed at the back page (except the police clearance)
-bring the completed work permit form with attachments to labor office and they will give you a schedule/endorsement letter for police clearance (they will not take your completed form or monetary payment unless you have the result of your police clearance)
-after a week when you have the endorsement letter from labor office you have to go to Police Clearing Office at Salwa, fill up police clearance form with requirements listed at the back, you could wait for a week or two for the result.
-lastly you have to go back to labor office with your
1. Completed work permit form with all the attachments (listed at the back)
2. Result of your police clearance
3. Payment

and in the same day they will provide you with your work permit ID

or you can ask the company's mandoop to do that for you(a lot easy :-))