What Greek would I be if I didn't share my spanakopita recipe. This is a staple in my family, let alone a fan favorite among most Greek food festivals.
In a large bowl, mix with a spoon to combine all the ingredients.
On a cutting board, grab 1 sheet of dough, and fold it in half. Using a knife, cut the dough into 3 long strips.
Using a spoon, add 1 spoon of Spanakopita mixture to the top-left corner of the dough sheet. Then, begin the fold the strip of dough like a flag. You should end up with a triangle-looking shape at the end. 
You have 2 options, cook as is, or freeze to cook at a later time. If you want to choose to freeze, just make sure you use plenty of wax paper in between layers since the dough is still fragile.
If you bake right away, place the Spanakopita onto a baking pan with plenty of spray cooking oil. Bake at 375-400 until crispy.