If not eating the crepes immediately, cool them on a wire rack first to allow steam to evaporate. If you stack the crepes when they're still warm, the steam will make the crepes wet (soggy). If you wanna stack the crepes, place a small piece of parchment paper between each crepe.
Store leftover (cooled) crepes in an air-tight container in the refrigerator for 4-5 days. For longer term storage, freeze in an airtight container with a piece of parchment paper in between each crepes (so they don't stick together as they freeze) for up to 1 month.
*I used a little over 1/2 cup (45 g) of rolled oats and ground them in a blender into oat flour.