Visit the island with your car on a tourist visa. When you arrive at the port of Valletta, ask for a six-month pass for your car. You are legally allowed to keep it on the island for six months. Keep this piece of paper with you to show if you are stopped by the police. Make sure your insurance papers are in order, and that the road tax from your country of origin is up to date. Your car can be legally impounded if these are out of date, and you will have to pay a daily fee. When your six months are up, you will have to take your car out of the country for at least another six months or pay the required import duties.
Get a working visa if you are planning to work in Malta and want to keep your foreign car legally on the road. You are then entitled to use your car for the length of your work visa. Work visas are usually renewed annually. Take a copy of your passport, your signed work contract and work visa, the car's registration papers, a copy of your car insurance and road tax disc to the Department of Transport in Floriana. They will give you papers to fill out and issue you with a disc to put on the windscreen, showing you are legally allowed to drive your foreign vehicle on the island. Bear in mind you are not allowed to lend your car to anyone else. You are the only allowed driver. You still have to make sure your own country's tax disc is up to date and your insurance is valid.
Apply for permanent residence. When this is accepted, you are allowed to bring in one foreign vehicle per person. This is tax-free, so you are allowed to change your foreign plates to Maltese ones without incurring import charges. However, when you sell the vehicle, you will be liable to pay the duty on it. Take your permanent residence papers, passport and car's papers to the Department of Transport in Floriana, and they will register it as a Maltese car with new papers and you will get a new Maltese license plate.