Like the kids' versions, grown-up Power Rangers come in a variety of colors to represent different Rangers. The easiest way to get the look is to purchase a premade costume complete with a one-piece bodysuit and mask/helmet.
If you're especially creative, you can mimic the look by sewing fabric patches onto a solid-colored sweat suit. Look for the Power Ranger gloves and masks at your local costume shop. Finally, consider dressing the entire family as Power Rangers. Don't forget to take lots of photos of your superhero family.