Start now figuring out the foods that may cause a cough, spicy hot food or chocolate are ones to watch out for. Soups and drinking a bunch of fluid help.
Keep plenty of ice water available and take small sips, warm it in your mouth to cool then swallow. Warm beverages like tea or coffee may help as well but if it's hot, allow it to cool before swallowing.
Avoid cold dry air and if it's a big issue for you, you might look into an inexpensive humidifier.
When mucus builds up which it will, lean forward and exhale with your vocal cords open.
Dr Haben will give you some really strong cough medicine that will last for seven days. Don't overdose on it because it's really bad stuff but if you have issues with coughing, request a second bottle before you leave. I only used one dose because Dr Haben suggested I do it before my flight and that was a big mistake, I wanted to put my head down and in the small seats center seat, there was no place to do it. By the way, you will have to check your bag with the cough medicine so you will need to take a dose before checking the bag.
Sleep on your side and use the pillow to keep your mouth closed. Breathing through your mouth will make you want to cough.
Start now learning how to suppress coughs. I spent the week before surgery resisting the urge to cough to reduce the risk of slipping up after surgery.
Most of all, the sutures can take some abuse and Dr. Haben's words are control the things you can and don't worry about the things you can't. The few failed surgeries I have seen so far were because the folds didn't heal together correctly and not because of suture failure however movement of the folds against each other might prevent proper healing.