If you find it difficult to stay focused in such long tournaments, here are some tips that have helped me: when the tournament is long and, obviously, has a fairly extended registration period (about 3 hours for late entries), I register at least halfway through that period. That's when I start playing. This helps me avoid feeling so tired after many hours of playing and prevents me from getting distracted. Another thing I do is take advantage of the 5-minute breaks. I step away for a while to clear my head, and, well, it might sound strange, but I like to do other things while I play, and I don't mean listening to music. It could be reading something, playing a game on my phone, something that doesn't absorb me so much into the game. I do this because I've realized that simply watching the tournament I'm playing in puts more pressure on me, and I make mistakes I shouldn't. Of course, I don't always do it, but these are small details that help me. I recommend you make small changes, try things that you feel might help you. This is what I did when I had been playing for a couple of years and started playing buy-in tournaments. I always registered from the beginning, and I couldn't handle playing for so many hours. Over time, I've noticed things and I've changed them, but every experience is different. That's why I recommend you make slight changes and test them. If something works for you, keep doing it; if not, stop.
