A visual aid device to provide a reference line for a golfer. The device has an elongated linear member held by opposing clips adapted for securement to the bill of a golf cap. The elongated member may be a stretchable elastic member or a rigid member to provide a reference line for a putter or wedge, for example, as the golfer addresses and strikes the golf ball. Spaced markings may further be utilized to provide additional visual aids to a golfer and advertising or logos may be applied to the clip members.