Cop stopped me for not signaling in very light traffic on highway

Sounds as though it was just your lucky day.

Why so lucky? Bored cop mebbe. Perhaps a cop who'd just gotten a talk about traffic violations that were getting lonesome and needed some attention. Or maybe he wanted an excuse to pull you over (perhaps to gauge whether you had viewed the bottom of a few beer bottles that night, or to come get a good look through your windows, or whatever), or thought you were somebody else of greater job related interest, and then felt, as a few cops do, that he couldn't let it go without writing you up for *something*. Who knows?

Anyway, familiarize yourself with the appropriate bit of the state vehicle code (there may be a citation of the applicable section on the ticket) and see if you think you did it and he got you dead to rights. I guess if he did, then you could decide whether to see if he shows up in court or blows it off.

Frankly, if a cop gets me fair and square on something minor, I don't waste his time or mine trying to hot-air my way out of the ticket, but I suppose it's worth seeing if he shows up. (This is seldom put to the test, as I try not to violate too many traffic laws, especially in front of the cops, but time and chance happeneth to them all...)

If convicted, see if your state has provisions for "traffic school" to remove any points from your record.

BTW, I try to remember to use the turn signals even when nobody's particularly nearby -- this makes it clear to other drivers (police or otherwise) that they're watching an intentional maneuver by a vehicle under control, rather than somebody dealing with a car malfunction, nodding off, seeing snakes, receiving commands from the mother ship, or other things we observe on the road. I would imagine we've all failed to do so, but it is a good habit.