Because of the delicate consistency of the shells, they are made using a piping bag to pipe them on to a baking sheet. This is as opposed to using a cookie scoop like a traditional cookie may be made with. To make these macarons in a heart shape, if you are skilled with piping, you can simply pipe them on to the baking sheet. However, for the rest of us, using a heart template that is placed under the parchment paper makes it easier to pipe hearts. The template is then removed before baking the macarons.