After a 3-mile warmup, form drills and strides, run 6 miles at 5 seconds per mile faster than your goal marathon pace. So, if your 26.2-mile goal pace is 8 minutes per mile, you aim to hold steady at 7:55s for 6 miles. After completing the first 6-mile segment, take 10 minutes to shed clothes, use the bathroom or jog around a little bit before going into another 6 miles at the same pace as the first: 5 seconds per mile faster than goal marathon pace. If you’re feeling good, it’s OK to pick up the pace a little bit—maybe another 5 or so seconds per mile—but you want to avoid racing the second 6-mile segment and compromising your recovery for the next workout a few days later, Humphrey says.

If you’re running a marathon this year and you’re worried about the task ahead, relax.We’re here to advise you on what to do a month out, a week away, even the day of. Shoe tips? Check. Hydration strategy? It’s here. Taper advice? Got it. And for those of you not running 26.2 this year, our humble (yet informed) opinion is that you will be soon. So keep these tips where you can find them – they aren’t just essential; they’re timeless.

Source: 26 Tips for Running Your Best 26.2