One solution that we all get tired of hearing, but is definitely affective is handwashing. You should wash your hands before, during, and after the handling of food, using the bathroom, when someone in your home is sick, and when in doubt, you should probably wash your hands.
Another prevention tip that coincides with handwashing is keeping your distance. Keeping your distance from students, family members, and friends that seem to be affected by the illness, is a helpful way to stay clear of the dreaded cold/flu. If for some reason contact is made, washing hands is always a good idea.
With students being in sports, it is also a good idea to stay clear of sharing food, drinks, and utensils. This seems to be a fast acting way to spread such illnesses. Also, with kids being in sports, it is a good idea to allow yourself plenty of rest.
Ways to prevent others from getting sick is staying home when you are sick. It may difficult, and missing school, a practice, or a game can be stressful, but it is the best way to prevent the spreading of the cold/flu. It may seem like a hassle, but using wipes and tissues is a good idea for those runny noses and germy hands. Live a healthy lifestyle, and seek medical attention to receive antiviral medications.
Info adapted from http://drliesa.com/fighting-the-flu-naturally-part-1/