Maintain good hygiene. Don’t switch temperatures too quickly. If you are in AC and have to go out. First switch off the AC sometime earlier so that the temp becomes normal and then step out. Temp extremes are harmful

Dress the baby properly.; Keep feet covered.; Ensure a thin blanket is used. Avoid bathing baby for too long. For you, eat healthy basically. And even if you have fever or Cold, Breastfeeding doesn't pass that on to the baby. So relax.

Eat well feed well. Cold and cough come from air or water borne mediums.. it's actually out of our control.. so rather be careful :)