I bring an ebook reader and read a good novel. The more interesting the better. After a while the droning voices from the platform just fade from consciousness as I get lost in the action of the novel. Set the font level to the smallest you can bear and prevent nosy folks from reading over your shoulder.
When I get tired of reading I take a break and nap for a while. My wife won't elbow me awake unless I start snoring loudly, in which case it's time for a bathroom break, when I come back to the seat it's always good to reach into the lunch box and get a snack or a drink, or maybe a piece of gum to chew while I go back to the novel.
For those stuck due to family allegiances and loyalties to the WT, I encourage the reading for entertainment and nap time during assemblies and conventions. I found this routine quite more bearable than trying to listen to the annoying nonsense being spouted from the platform.
One advantage of napping, especially during the last talk, which is usually by some Bethel heavy, is that if you can get a good nap, when it's time to drive the several hours trip back home you will feel a lot more rested.
So get an ebook and download a good novel.