This set is all about learning to pace yourself. After an easy warm up and a few drills, we're starting this with a 4 x 50 or 4 x 25 Freestyle (Descend 1 - 4). This means that your first 50 or 25 Freestyle is easy, number two is a little faster, number 3 is another little faster and number 4 is fast. Time yourself so you know exactly how much faster you go each time. Unfortunately, sometimes we put in more effort but don't actually go any faster because we start to slip in the water (losing your grip), so make sure you stay focussed on good technique and feel of the water.
During the main set, the distances get smaller. I love sets like this as the hardest part is done at the start and it only gets easier from there. Enjoy your swim!