Cold and flu are both in season now. Both are transferred in the same way. Usually droplets. This means that if you see someone coughing or sneezing, stay away from them as what is spewing out of their mouth or nose could and probably does contain cold or flu virus. They should try to stay home for other's protection as you are contagious for about a week. But if out, they should cough into elbow and same for sneezes or cover with something when sneezing or coughing. Cold and flu virus will live on a Kleenex for about an hour, on their hands for about two and on a hard surface for up to 24 hours. Ugh. Cleaning surfaces with cleaning wipes will help. And cleaning your own hands is essential. Proper hand washing and/or using hand sanitizer should be routine. Then basics like getting enough rest, exercising regularly and eating well will help you. That's the skinny on trying to avoid cold and flu. Good luck (hope it works)
(oh, and flu vaccine is good to do and if you are immune compromised, a mask helps).