Check it frequently. Keep the bike in gear for quick response when stopped in traffic. Even when you are stopped, continue to check your mirrors for potential hazards approaching from the rear. If it appears that the approaching vehicle is not going to stop in time, you need to be able to instantly launch your bike out of harms way. It is best to position yourself near the outer edge of the lane to allow you to dart either left or right.
More lights are better than fewer lights.
It is a relatively inexpensive way to give you the extra edge for safety's sake. Members participated by offering their own tips on things that they found useful. Evi suggested to watch the front tires of the vehicle to predict a sudden lane change before it actually occurs. That tire will telegraph the move and provide you with that important fraction of a second to react and execute your diversion.