1. Drink LOTS of water. Lots. Did I say lots? That thins everything out so your body can eliminate it easier. TMI, I know, but really, it is one of the most effective things you can do and it's cheap!
2. Get a good antihistimine, in case it is allergies. I prefer Zyrtec (or the generic equivalent). Claritin works great for some folks. If you go with the Zyrtec, take it before you go to sleep at night - it can make you a bit drowsy initially, this way you just sleep through that part and wake up in the morning ready to go.
3. Get some zync losenges (ColdEeze or something similiar). This can help cut the duration of a cold, if it is one.
4. I find Mucinex DM works fabulous for the coughs I get. And I get a lot. Just have bad lungs I guess.
I am also fighting the start of what feels like a cold - and we leave on Friday
But I am doing all of the above (esp #1) and feel like I am getting the upper hand.
Oh - and if the cough is a regular thing, esp at night, go to your doctor and get checked for asthma (potentially allergy induced). Many people develop it as an adult.