When the assigned button is pressed, the watch hands will come together. Depending on the model, you may need to look at the opposite end of the minute hand. The hands should point to 0 on the dial on your watch. It will then sweep between 0-100 to display your current percentage progress to your daily step goal.
e.g. If your daily step goal is 10,000 steps and you are currently at 2,000 steps, the opposite tip of the minute hand will point to 20, meaning you are 20% of the way there.