You may have noticed the white dashes on the highway. Those denote lanes, one per car. If you wish to no longer be in your lane, but instead prefer another lane — say, for example, mine — you are free to move under specific circumstances.
First, take a look at your destination lane. Other cars will be in it. You need to identify a car-length gap between those cars (again, you do this by way of looking at the lane). Second, notify other drivers of your intent to occupy the gap you’ve identified. The traditional method of communication between drivers is, ironically, not an angry hand gesture. Instead, try using your blinker.
These rules apply to all drivers. Even you. You moron.