The biggest thing you can do is ride is with the assumption that every car driver has the potential to not see you. Make eye contact with the driver, for example at junctions, if you can. Second guess their moves in where they are looking, if they are looking in the opposite direction, get ready to take evasive action.
Always ride with a rear facing mirror, use this to monitor traffic overtaking you. Get use to the expected position of the car as it approaches from behind, if it's not pulling out wide or slowing down, get ready to steer into the nearside to give you as much chance as possible to avoid being hit.
Ride with confidence, make your presence known at junctions, roundabouts, traffic lights etc, again make eye contact with drivers, check they have seen you.
I always wear some hi viz, and have multiple rear lights and a helmet light. I always run front and rear lights during the day too