Whenever I travel, I try to learn a few basic words in the native language. At the very least, I try to learn “please” and “thank you”. I may be butchering the language but I’ve often received a warm response when the person sees that I’m making a genuine effort to communicate.
One really simple solution is to try using a free app called duolingo. It has a ton of different languages that you can learn all set up in an easy game style format. I bet you can teach yourself the absolute basics in a few minutes while on your flight. At the very least, it’ll give you something to do while waiting for drinks to be severed. You can also do a test run at the airport. Try buying something small and just practicing.
Of course, you can always resort to the smile, point, and nod method if needed.
The absolute worst thing is play into the “ugly American” stereotype of speaking slower and louder when someone doesn’t understand you. If anything, math and love are the universal languages, not English.