Do your research, so that you can make sure that LoJack is an investment that you want to make. Not only that, but determine whether you want the additional Early Warning system that places a call to your cell phone if your car is moved without a key for it.
Call the dealer where you bought your car, truck or SUV (or the dealership that you're thinking of using for your next purchase) and ask if they install LoJack. They do? Great, let them know you're interested in the system and set up an appointment for an installation.
The dealer you're working with doesn't offer LoJack? Call around to other dealers in the area to ask if they do. Choose a dealer that is convenient for you and set up an appointment for an installation of the system.
No convenient dealership that offers LoJack in your area? Give their customer support team a call or contact them via their website. Talk out your needs and schedule a time when one of their representatives can come to you to install the system.
No one that can come out but you still want the system? Determine how far you're willing to drive to get the system installed; make some phone calls to find a dealership and schedule an appointment for an installation.