Trouble understanding the path factor of Right Effort The path factor Right Effort in the noble eight-fold path contains 4 steps which are;


Prevent the unwholesome that has not yet arisen in oneself.
Let go of the unwholesome that has arisen in oneself.
Bring up the wholesome that has not yet arisen in oneself.
Maintain the wholesome that has arisen in oneself.


I understand 1, 3 and 4 but have trouble understanding no 2 - "Let go of unwholesome that has arisen in oneself".

Is that done by using the noting-technique and then observing and noting the phenomena until it disappears?

Or is it that when e.g. anger has arisen and other techniques dont work then one uses Metta meditation as an anti-dote?

Thank you for your time.

Lanka
There're different antidotes to the different unwholesome states that arise. Ven. Bodhi in his "The Noble Eightfold Path"'s Chapter 5 wrote:


  For desire a remedy of general application is the meditation on impermanence, which knocks away the underlying prop of clinging, the implicit assumption that the objects clung to are stable and durable. For desire in the specific form of sensual lust the most potent antidote is the contemplation of the unattractive nature of the body, to be dealt with at greater length in the next chapter. Ill will meets its proper remedy in the meditation on loving-kindness (metta), which banishes all traces of hatred and anger through the methodical radiation of the altruistic wish that all beings be well and happy. The dispelling of dullness and drowsiness calls for a special effort to arouse energy, for which several methods are suggested: the visualization of a brilliant ball of light, getting up and doing a period of brisk walking meditation, reflection on death, or simply making a firm determination to continue striving. Restlessness and worry are most effectively countered by turning the mind to a simple object that tends to calm it down; the method usually recommended is mindfulness of breathing, attention to the in-and-out flow of the breath. In the case of doubt the special remedy is investigation: to make inquiries, ask questions, and study the teachings until the obscure points become clear.