It's actually far more dangerous. Motorists do not expect a bicycle on the sidewalk, especially coming out of driveways. You are also endangering the lives of pedestrians, including those with disabilities, who have a right to the sidewalk. If you must use the sidewalk, walk your bicycle. Reflectors alone will not do.
Yellow lights are best for the back as they stand out more.
Also a relective bicycle safety vest is helpful. People who bicycle without lights and in dark clothing are an accident waiting to happen. The last thing you need to happen is for your breaks to fail when you need them most or your chain to break or some other important part. Be alert at all times. Do not have earphones on.