I repeat this cause people rarely mention these tips:
1- Your nose is a spaceport for the virus if not dry; it will try to cause you to sneeze to spread to other hosts. Keep your nose dry. If you live in a cold country, breathing will cause condensation in your nose. As soon as you get inside, go wipe the inside of your nose with toilet paper or tissue paper to get the moisture out, wash your face a bit, then wash your hands. Do NOT blow your nose! You'll spread germs. Just wipe the inside of your nostrils.
2- Your ears are an infection pathway! Never put your fingers in your ears and don't let water in! When you take a shower you must use earplugs and if you don't have any use toilet paper or tissue paper. If you get some water in, lean your head sideways to get it out, but don't touch the inside of your ears and don't use q-tips either!
3- If you take a shower, keep water out of your mouth/throat! The speed pf the spray can cause water to stuck in the back of your throat, which can favor infection just like your nose being moist. It's not uncommon to catch a cold soon after accidentally getting a spray of water in the back of your throat.
4- Stay warm, the immune system is weaker when it's cold to save energy since pathogens are usually less active in the cold, but we live in a world where the temperature can fluctuate wildly due to modernization, our immune system doesn't necessarily adjust itself that quickly.