I assume that the rules of the road where you are, are the same as in NY and entering traffic is supposed to yield to traffic in the circle.

If so, understand that a certain percentage of drivers don't. Either because they don't know the law, don't care, or don't look. Here there's a large circle on a bus route (more than one actually) Buses are routinely cut off by entering drivers. Obviously they saw the bus (how could they not) but entered anyway.

While anything you do to help yourself stand out day or night will help, it isn't absolute protection because as the buses prove, some drivers don't care anyway. I ride through the same circle on my bike, and as I pass the entering points, I eyeball the driver and gauge his intent. If he wants to cut me off and enter, I adjust speed and position and let him. This isn't common, and most drivers are OK, but my point is that you can't count of drivers not to hit you, you have to make them not hit you by anticipating and adjusting.

IMO traffic circles are actually safer than other intersections because most offer good sight lines and plenty of room to adjust, but you can't passively assume everybody will play by the rules.