To make mix baking soda with little bit of water and some vicks rub(if it is for a kid use baby vicks)
Make into a ball and place in freezer. Once hard you can store it for a time when needed or use right away. Use in a warm stem shower to help relieve cough and nasal congestion.
Note~ Make sure not to steps on it as it melts as it can be slippery. I have not had any issues with my 4 year old slipping or me but use with caution. Best bet is to put it behind you in the shower so the vicks is not running under foot.
You can also add in some other oils that may help like lavender. In this bath bomb we put in dried lavender to help relax.