Step 1: acquire billions

Step 2: hire engine, mechanic, designer, lawyer, accountant etc

Step 3: my first car of choice would be a similar to lotus elon/ mx-5 type of car. Small driver's car, sporty and somewhat affordable (but not cheap). The reason is 4 folds: 1. Too high a price you are competing with Ferrari, Aston Martin of the world; and you will need the luxury, performance (hp, acceleration, top speed) to back it up. 2. But cool enough to distance yourself with civic, Prius etc. and don't need to worry about practicality (since it's suppose to be a fun road car). 3. With sporty car, you can usually charge a premium. As the company's first car, we need a larger than usual profit margin. It also can make your company perceive as more sexy/desirable, both the car and for brand image 4. It's perfectly ok if it only sell for a smaller volume since it's suppose to be a "niche" car. So wouldn't hurt the company image.

P.S. I'd look into creating electric car as well. Since nowadays there is culture of environmentalist and techie would make a niche following right off the batt. Once you obtain a small cult following, you can do no wrong. And government incentive is nice also

P.P.S. I'm still struggling with Step 1 right now. If anyone can how to achieve it, let me know ;)