Encircling the grave:[1]

Many have the custom of encircling the grave.[2] The Rebbe would circle the grave one time prior to leaving.

Taking off the shoes:

As a sign of respect it is accustomed to remove the shoes prior to entering into the Rebbe’s Ohel.

Placing a hand on the grave:[3]

Many are accustomed to place a hand on the grave upon praying [see next regarding Hishtatchus]. One is to place specifically his left hand on the grave.

Hishtatchus:[4]

This is the general term used for the Mitzvah of visiting a Tzaddiks grave. It literally means prostrating, as the ideal Mitzvah of being by a Tzaddiks grave is to prostrate oneself over the grave and recite prayer. It is for this reason that many are accustomed to try to at least touch the grave while visiting.

Maana Lashon:[5]

It is customary to recite a compilation of Psalm’s and prayers entitled “Maanah Lashon” upon visiting a gravesite of a Tzaddik. There exist various dialects of this compilation.[6] The Chabad Nussach of Maaneh Lashon was compiled by Rabbi Dov Ber of Lubavitch, known as the Mittler Rebbe, on occasion of his visits to the burial site of his father, Rabbi Shnear Zalman of Liadi, in Haditch. This Maaneh Lashon was reprinted by the Rebbe in the year 1950 shortly after the Histalkus of his father in-law, the Rebbe Rayatz.[7]

Placing a stone on the grave:[8]

Many have a custom to place a stone on the grave prior to leaving. The reason behind this custom is to leave a sign that one had visited the grave, out of respect for the dead. [It was never witnessed that the Rebbe placed a stone on a Kever.[9]]