As bsml stated it is important to determine the reason for the mucus forming.
That being said, the mucus can be "thinned" by use of the expectorant guainefesin, which comes in a liquid and time-release pills.
Drink lots of fluid after taking this medication.
Hello and welcome to the community.
That would really depend on what is causing the mucous. It can be from reflux in which case, controlling that will reduce the mucous. If the cause is allergies or asthma those need to be controlled.
You can have reflux without the typical heart burn symptoms.
I suggest that you see your doctor for a propper diagnosis so that you can be on the correct preventative medications and/or life style changes.
Take care and God bless.