Get out a large mixing bowl and add the sliced sugar snap peas, sliced radishes, and the cup of arugula to it.
Make the dressing: Get out a small mixing bowl and add off of the ingredients for the dressing to it. Then use a whisk to mix and incorporate all of the ingredients together.
Pour the dressing over the snap peas, radishes, and arugula. Use two large spoons to toss everything together and serve immediately.