Place sushi mat, with slats running parallel, on work surface. Place 1 nori sheet, shiny side down, on mat lining up 1 long edge of nori sheet with edge of mat nearest you. Use moistened fingers to evenly press half the rice mixture onto nori sheet, leaving 1-3/4-inch border on long side of nori sheet farthest from you. Place half the shrimp mixture in even row 1 inch from bottom of nori sheet; place half each
of the cucumbers, carrots and avocados in rows next to shrimp.