You may think that riding against traffic is the safest option so that you can see all oncoming cars. This is not the case. The safest practice is to ride with traffic. Drivers are expecting to see cars and riders in their lane so they are looking out for them. Drivers are not looking for anyone in their lane riding towards them so they are less likely to see a rider facing them. Also, if there is a collision, the impact may be less if you are going in the same direction as the vehicle that hits you.