Gate warning signs can be very necessary to give urgent information to passers-by or to drivers. As such these signs need to be relatively large so as to be viewable from afar. It is usually a good idea to include a warning or caution label to the sign depending on the information being given just to grab attention even more. Yellow, red, orange and black are good colour schemes for this type of sign, all placed on a white background. Graphics can be included for extra information and clarity.