Well, there is nothing you can do to completely negate the chance of being struck by a vehicle while riding on roads. The best you can do is make sure to obey all the rules of the road. Treat your bike like you're a car ... stop at red lights and stop signs, yield to right-of-way when making a turn, and always make sure to stick to routes with bike lanes. Doing all of those will never guarantee that you'll not be hit by a car, but they give you the best chance to making it home safely.