I’ve gotten into the habit of tapping my brakes when I have traffic behind me and I’m about to initiate a turn or there’s congestion or an obstruction ahead. Motorcycle turn signals are entirely too small and hard to see. Tapping the brakes blinks the brake lights and can help get you noticed. There’s nothing worse than hearing the squeal of brakes behind you because an approaching driver didn’t notice you.
Modulated tail lights are a good idea too. The kits don’t cost much and they can be programmed to flash at different intervals. Every time you apply the brakes the lights flicker at a predetermined interval.