It can be overwhelming to think of running 26.2 miles (or 42.2 kilometers!) all at once. So divide the marathon into smaller segments. Focus on each mile at a time. If you’re aiming for a specific time goal, focus on attaining that goal at each mile checkpoint.
For example: if you want to break 4 hours, that’s 34 seconds per 100m pace. So focus on running:
the first 100m in 34 seconds,
the second 100m in 34 seconds,
the third 100m in 34 seconds,
the fourth 100m in 34 seconds.....
I've done this many times with great success.
How do you guys split up your marathons?