There is a bit of a paradox about the feeling exercise. If you let go of the labels what is it you feel. A distant buzz in your finger tips, a tightness in your stomach... without labeling it... what shape do you imagine the tighness of skin has?
Here you need to notce. I feel depressed....
How do you know that you feel depressed? It's just an abstract word that describes the feeling. So forget the word. What does depressed feel like? If can't be nothing because you labelled it!
If you're feeling frustrated, check it out how do you know that feeling is frustration and not gladness? What is it that makes that feeling depression? That my dear friends is a paradox. The label means exactly the same as imagining what colour it is what shape it is... then will notice some about the feeling, there is a vibration, (all vibration really is is movment).
If you're really lost feel the air moving through your nose as you breath. Have you ever felt an itch? Follow it... how do you know it is an itch? really feel that.
Be there in the now with whatever physical or emotional feeling that you are aware of.
One word of advice, take it lightly. It's really just training of bringing yourself to the here and now. If you itch... notice that you're feeling it before you scratch it.
Alex