Reb Hillel Paritcher once explained that to live the life of a chossid, one needs two vital things:
Every single Jew who wishes to go in the ways of Chassidus needs to be mekushar [bound] with the Tzaddik of the generation, such as the Rebbe. He should also acquire for himself a teacher, who is a chossid, to teach him and explain to him well the teachings of the Rebbe and [to explain to him] all of Chassidus. For the Tzaddik elicits the level of seeing G–dliness into one’s soul [which is the level of Chochmah], while the chossid elicits the level of hearing G–dliness into one’s soul, which is the level of Binah. This will suffice for the understanding person.
Migdal Oz, p. 353.
In my own words: It is not enough to study Chassidus and follow Chassidic customs on one’s own. In order for these things to have their desired effect, one needs two forms of outside help:
1. Hiskashrus (a bond) with a Rebbe. Since the Rebbe himself sees G–dliness, he is able to make makes the G–dliness one connects with through learning Chassidus real; this is the idea of “seeing” G–dliness, as it were (see here).
2. A chossid to guide him and explain the Rebbe’s teachings to him—what is today referred to as a mashpia (as distinct from an asei lecha Rav—see here). This enables the Rebbe’s teachings to permeate the chossid intellectually. This is the idea of Binah, which is the idea of attaining abstract understanding of G–dliness. This is compared to “hearing” G–dliness, just as one hears about something that is distant.
This guidance also seems to be needed in order to guide the person in applying the teachings to himself personally, for the purpose of learning Torah in general and Chassidus in particular is to affect one personally. On the contrary, this is the true measure of whether these teachings have indeed permeated him.