Work up to your max weight for:
Sandbag Back Squats 5x5
Sandbag Overhead Press 5x5
Take a 3-5 minute rest between each set of exercises. The weight of your sandbag should be such that you struggle to complete repetition 5 in each set.
Record your weight.
Plus, if you're following the Milo Experiment then you should be on Day 6. If you haven't yet started and you want a simple way to build your strength then check out the post here