It all depends on your employer. If your employer is competent enough then what he should do is gather all required documents for applying visa and work permit then take you to department of Labour on Monday to submit the application. If labour office accepts the application they will give you a waiting receipt to pick your work permit in about 5 to 7 days. You can use the receipt at immigration as prove that you will get the work permit and they extend your visa as per the employment period indicated in the work permit receipt.