This might sound a litle extreme, but in fact is not: a proper distance between you and the other vehicles on the road is a matter of live or die. So, why take the chance? Do never allow your self to get "boxed in." A proper space creates time and helps you avoid collisions. Maintain at least two seconds of following distance, more if posible. Adjust your position in traffic as necessary to avoid driving in others’ blind areas. Don’t allow yourself to be tailgated-change lanes or adjust your speed to encourage tailgaters to pass you.
By not keeping a proper distance you won’t only put yourself in danger, but also everyone else on the road. Well, but how can you know you are not to close? A simple example to know that you keep the 2 seconds distance: watch as the vehicle ahead passes some object-I often use shadows or marks on the road surface-then count "one-thousand-one, one thousand two." If you pass that same spot before getting to "two," you’re too close-back off!
But not all the time this 2 seconds are enough, so this is the minimum distance, but do not avoid to leave more space when you can! And the most important more space is necesary if the vehicles next to you has different characteristics than yours - motorcycles or trucks, and off course if road surface is slippery.
It is not a waste of time if you drive a mile or two per hour slower than traffic flow: the traffic will slowly pulling away from you, helping you to maintain the space. In order to do this keep to the right (actully there are states where this is the law for the slowers drivers.)
Try to adjust your speed and keep your vehicle "in the open" with no vehicle to the left or right (as much as posible). A very unconfortable feeling on the road is then you are beeing "packed", so why not to avoid this feeling?
Just remember: a good distance is very important for your safety and the ones in your car, children especially and for the ones next to you on the road.