The switch on or near your steering wheel is called a "turn signal." It's there to help you signal to other drivers when you are going to be changing lanes or turning. It is not, in fact, optional. In fact, I do believe it is required by law. Please (re)acquaint yourself with this device before you venture out onto public roads again, or else next time I will let you hit me and then sue you for being a terrible driver.
Also, lights on when raining or when visibility is limited (which means at sunset).
Where did you people learn to drive?
No love,
- stonebiscuit
P.S. This applies triple for police/deputies driving marked cars. For heaven's sake.