In times of uncertainty it is difficult to dig through piles of information from which only some are relevant and many are even simply misinformation, may it be intentional or not. The World Health Organization (WHO) is one good source to inform yourself though.
The WHO states, “If you do not have any respiratory symptoms, such as fever, cough, or runny nose, you do not need to wear a medical mask. When used alone, masks can give you a false feeling of protection and can even be a source of infection when not used correctly.”
When to wear a medical mask, how to wear it and why to wear a mask is explained in this very short and informative video by the WHO below. Please also note that making your own (DIY) mask or buying a “stylish” mask might not be useful and if you are looking to buy, you can search for the reference “N95 Respirator” and beware of fraud and overpricing. Make sure it has the metal clip on the nose as well.
Personal opinion: Despite that, wearing a mask could possibly help you from getting infected to some degree, but the research on the subject is still young. Better than going out into the public with a mask on is to stay at home as much as possible and help to flatten the curve. More information on COVID-19: Coronavirus disease (COVID-19) Pandemic
YouTube: When and how to wear medical masks to protect against the new coronavirus?