A red spot in the eye can appear without any apparent cause for it. It could be a result of coughing or sneezing too hard so there isn’t really a way to usually prevent the appearance of a red spot in the eye, but there are certain precautions that could be taken in order to prevent more uncommon causes for it. These tips include being careful not to rub your eyes too hard, wear protective gear if your eyes are at risk for an injury and keep your contact lenses clean. Also, if you have a bleeding disorder, consult with your doctor how to keep it under control.