One of the activities that can either be a trap for getting lost in thinking and reactivity or, instead, a great opportunity for mindfulness practice, is driving. Different types of drives present different practice opportunities -- longer drives on a highway with moderate or light traffic unfold at an almost "meditative" pace. Shorter drives around town to do errands throw a lot at you in quick succession. On those longer drives, the best opportunity may be when driving by yourself, or with one other person who's either reading or otherwise occupied.
One approach is to be primarily mindful of the body and the interplay between sight, hearing, and physical movement. It's possible to touch into a sense of the entire body and mind acting in concert while performing this complex activity. In a very light way we can be aware of the role vision is playing, how the body is responding with subtle or large movements, and the degree to which the body is relaxing or tensing up. Depending on circumstances, it can be possible to "abide" in this restful but very aware state for some period of time.
It's not uncommon, however, for the mind to require something a bit more engaging to keep it interested. As long as we are experienced drivers, it's very likely the mind is already quite busy thinking, so it makes sense to bring our awareness to that. You may notice a lot of judgment and comparing thoughts about other drivers going through the mind. You may notice feelings of satisfaction when you are able to, for example, pass a slow moving vehicle with ease; conversely, you may notice feelings of somehow "losing" when other vehicles pass you, or otherwise "get ahead". It can be pretty surprising to see the degree to which fairly illogical ideas in the mind can actually drive our mood and actions -- how, if these ideas go unnoticed, we can in some way just be "along for the ride". Even if we are the ones driving!