A little warm up and a good long Sunday morning rucksack march. Go as fast as you can without running. Go over varied terrain and learn to use the downslope of the hills to make time. As always be sure to stay hydrated during the march. It should be a habit that will carry over to Selection and training afterward.
Becoming dehydrated during a long training event such as a ruck march or long-range movement is a guarantee for bigger problems and failure, keep sipping on the water during the course.
Training:
Warm up
20 Pushups
20 Sit ups
8-mile rucksack march over varied terrain. Try to keep your pace better than the standard. And mark your times in your workout log book.
Stretch well after completion