I,40: Who calls us Thelemites will do no wrong, if he look but close into the word. For there are therein Three Grades, the Hermit, and the Lover, and the man of Earth. Do what thou wilt shall be the whole of the Law.
Thelemites are expected to interpret the book for themselves, based on Crowley's commentaries and other writings; but are enjoined from promoting their personal interpretations to others.
Not every Thelemite utilizes all the practices available, there is considerable room for each individual practitioner to choose practices which are suitable to his or her individual needs.
Thelemites often take mystic names or "magical mottoes" for themselves as a sign of commitment; and customarily greet each other with the phrase, "Do what thou wilt shall be the whole of the Law"; to which the customary response is, "Love is the law, love under will".