Again this morning on NPR, I heard a recommendation from a doctor that we cough into our elbows instead of our hands. The reasoning is that if we cough into our hands and then touch something, the virus can be transmitted, and this is good reasoning. The virus can stay there until we wash our hands or use a hand sanitizer.
But if you instead cough into your sleeve, the sleeve has the viruses instead of the hand, so it can transfer to anything your sleeve touches, such as the kid you hug or the notebook you cradle in your arm.
It seems to me that the best way would be to cough into a tissue and throw it way, or to cough into your hand and then wash your hands. Hands get washed much more often than elbows or sleeves.