The following procedure can be used for Self inquiry:
As explained earlier there are 5 shells and Atman is beyond these shells. The innermost shell is Annamayakosha (body), then there is Pranamayakosha (breath/energy), the next one is Manomayakosha (mind), the penultimate one is Vijnanmayakosha (intellect) and the outermost one is Anandamayakosha (bliss). Atman (Self) is beyond Anandamayakosha. Let us now negate each one of these by Self inquiry.
Negation of Annamayakosha (body), Manomayakosha (mind) and Vijnanmayakosha (intellect) can be done by following the logic mentioned here which is based on the principle that if you are the witness to something then you cannot be that thing.
Negation of Pranamayakosha (breath/energy): Air is inhaled from the atmosphere and exhaled back into the atmosphere. Something that is borrowed from somewhere and given back to it after its use cannot be me. Morever, there is no intellect associated with breath/energy which I have and hence I cannot be Pranamayakosha.
Negation of Anandamayakosha (bliss): Sometimes I feel bliss after getting up in the morning after deep sleep. This also happens after listening to soul stirring music. Anandamayakosha is said to contain the reflection of the Self. This means that I reach the reflected Self when I experience bliss. Since I am the experiencer/knower of the bliss and every other kosha, I am beyond all of them and hence I am Atman/Self.