HELEN — When most people think of Mardi Gras, they think of New Orleans, brightly colored costumes and elaborate floats crowded with people flinging beads and candy into the crowd. The annual Fasching River Parade and Party held in Helen each year is its own early Mardi Gras holiday, a time to put on your most outrageous costume, pour a glass of schnapps and tube down the Chattahoochee River. At Saturday’s festival, participants and attendees left green, yellow and purple feathers, beads and other accessories in their wake.