Follow the instructions on your spring roll wrappers. Listing mine out here for your convenience.
Pour lukewarm water into a large bowl. Dip a summer roll wrapper into water for about 15 seconds. *If the entire wrapper doesn't fit into one bowl, dip one edge in and rotate until the entire wrapper is wet.
Once the wrapper can bend without breaking, remove it and place it on a clean work surface. You don't want the wrappers to become too soft as they may break. Make sure they still have some structure when you transfer them to a work surface.
Place about 4-5 cilantro leaves onto the center of the wrapper.
Starting with the side closest to you, add 2-3 slices of each vegetable in the order of: red bell pepper, carrot, yellow bell pepper, scallion (to taste, can be spicy), avocado, zucchini, cabbage. If you don't care about the order of things, you can also layer ingredients on top of each other.
Take the side of the wrapper closest to you and begin gently rolling the filling. Roll it about halfway towards the center, then fold the left and right sides of the wrapper towards the center (kind of like a burrito). Continue to roll it all the way up until all the filling is tucked into the wrapper.
You can plate it like this, or wait a minute or so and then slice the roll in half. *If making ahead, do not cut in half.
Return to the sauce, remove it from the heat. Over a bowl, strain out solids with a fine mesh strainer. Pour sauce into a bowl and serve with the summer rolls.