To install your infant car seat base the very first thing you should do is grab your car seat manual as well as you vehicle's instruction manual. And understand all of the rules, regulations about where you can install that car seat in that particular vehicle. Particularly for the weight of your child. If you have a preemie you might need a foam special instructions for a child who's really underweight. In general we recommend that you first try to install the car seat in the center of your vehicle. The safest place is in the back seat center. Only if you can get a correct installation there. It's a common miss known a lot of parents think that it has to be in the center at all cost. But if you don't get a good installation in the back seat center you should not leave it there. Most cars do not have luge equipped for the center seat so you have to install for the car seat the seat belt in that center position. If you have trouble with the vehicle seat belt because it's tilting, you can't get it tight enough, any number of problems then it's much safer to move to a side passenger seat and use the luge as equipped on the car seat so you can get a really tight and firm installation. It's really important when you are installing the car seat to make that it doesn't move more than 1" side to side. And that is right where it connects into the backseat at the lodge on the seat belt level. At the edge of the seat where the baby's head would be, that part should be loose because you want that to be able to move with the baby's head in the event of a car accident. So just because it feels very loose on this end doesn't mean that the car seat is too loose overall.