There are specialty stainless steel cone shaped implements for making wontons into a conical shape. Wontons wrappers are easy to use in any shape for hors d'oeuvres when cut and fried or baked with oil.
Pick through the crab meat to be sure there are no shell fragments or cartilage pieces. Squeeze out the excess moisture and place the crab in a bowl. Combine the crab with the mayonnaise, green onions, and lemon zest. Season to taste with salt and cayenne pepper. If the mixture is too wet to hold together add some panko crumbs to help absorb some of the moisture.