Make vinaigrette below and set aside.
In a large bowl, combine arugula and pumpkin seeds. Toss with vinaigrette, to taste.
Portion arugula and pumpkin seed mixture onto plates. Top each plate with watermelon cubes, feta and a touch of mint.
Drizzle each plate with a bit more vinaigrette.
Vinaigrette
Combine all ingredients through shallot in a small bowl. Stir briefly together.
Slowly drizzle in olive oil, whisking constantly to emulsify. Add salt and pepper to taste.
Alternative: add all ingredients to a high-powered blender and blend until incorporated.