Bring a pot of water to a boil and add 1 teaspoon of salt to it, along with the cleaned shrimp. Boil for 2-3 minutes, then drain the shrimp. Once cooled, slice each shrimp in half lengthwise. Set aside.
Fill a shallow, round dish with water. Take a rice paper sheet and submerge it completely in the water for 10 seconds, then remove it and place it flat on a clean cutting board or kitchen towel.
Working quickly while the rice paper is still wet, place one lettuce leaf toward the bottom of the rice paper. Place a few sliced cucumber and carrots and a few mint leaves on the lettuce.
Wrap the bottom edge of the rice paper over the filling (refer to the pictures above), and then place both sides over it (like a burrito). Roll it up once more and then place three pieces of sliced shrimp in the middle, side-by-side. Continue rolling the rice paper over the shrimp until the whole roll has been tightly rolled up.
Repeat steps 2-4 with the remaining rice paper until the rice paper and filling have been used up. Serve immediately with your chosen dipping sauce on the side.