I hear this in yoga all the time, and it took me a while to make sense of it in class:
Let go of your mind telling you this pose is too hard.
Let go of your worry that you only and always get injured.
Let go of that feeling of despising your teacher because she’s making you hold utkatasana for too long.
It has taken me even longer to internalize this outside of class:
Let go of needing to keep the apartment immaculate.
Let go of expecting yourself to conquer difficult recipes.
Let go of the idea that you have to be perfect.
Let go of the thought that you are not enough. Because you are.