There is a minhag to read from Tikunei Zohar, during the month of Elul, and to try to finish it by Yom Kippur. (Sichos HaRan 294, Mateh Ephraim 581). Tikunei Zohar is a part of Zohar, written by Rebbi Shimon bar Yochai, consisting of seventy chapters on the first posuk of the Torah. According to Reb Nachman of Breslov, although the Zohar is extremely holy, the holiness of Tikunei Zohar is even greater. (Chaye Moharan 359)
Many tzadikim say one should read Zohar or Tikunei Zohar, even if you don't understand anything, because it is very beneficial to the neshama. Among those that said this or similar statements to this are: Chida, Siddur of R' Koppel, Degel Machane Ephraim, Shearis Yisroel, the Komarna, Pela Yoetz, R' Moshe of Kobrin and Shomrei Emunim. A parable, in regards to reading Zohar without understanding, given by the Degel Machane Ephraim is: "One who enters a perfumery, even if he doesn't take out anything with him, will certainly leave with a pleasent fragrance on him." The Shomrei Emunim says that reading Tikunei Zohar is like a bath for the nefesh.
Here is an edition of Tikunei Zohar arranged so one can start at the beginning of Elul and finish Yom Kippur.