Surviving an 8-hour flight is all about proactive comfort management and staying ahead of physical fatigue. First, hydration is critical; the cabin air is extremely dry, so aim to drink at least 8 ounces of water for every hour in the air while avoiding excessive caffeine or alcohol, which can disrupt your sleep and cause bloating. Second, focus on circulation; wear compression socks to prevent swelling and make a point to stand up and walk the aisles or perform seated "toe pumps" every 90 minutes to reduce the risk of deep vein thrombosis (DVT). Invest in high-quality gear, such as a memory foam neck pillow, a contoured eye mask, and noise-canceling headphones, which are essential for blocking out the constant 80-decibel hum of the engines. Finally, curate your own "analog" entertainment like a physical book or a downloaded podcast to give your eyes a break from the blue light of the seatback screen. By layering your clothing to manage the unpredictable cabin temperature and following the "eat when they eat" rule to help reset your internal clock, you can arrive at your destination feeling functional rather than depleted.