During the month of Elul we are to prepare ourselves for the period of the High Holidays, which begins with Rosh Hashana, continues with Yom Kippur, and reaches its culmination on Hoshana Rabba, when the final judgment is rendered. It was on Rosh Chodesh Elul when Moshe ascended Mount Sinai to beseech the Almighty to forgive Benei Yisrael for the grave sin of the golden calf. Forty days later, on Yom Kippur, God announced His forgiveness. Thus, this forty-day period has traditionally been a time of forgiveness, when God is if we are allowed to say such a thing in a "forgiving mood." It behooves us to take advantage of this unique period and do what we can to earn atonement for the wrongs we committed during the year.
It is proper to read works of Musar during the month of Elul. One recommended book is "Sha'arei Teshuva," the classic work by Rabbenu Yona (Spain, 1180-1263) describing the process of Teshuva. Other recommended works include Rabbenu Yona's famous letter about repentance known as "Iggeret Ha-Teshuva," and the Rambam's Hilchot Teshuva, which presents the various requirements of Teshuva. Another work, "Orchot Chayim," is divided into thirty sections, which many have the practice of studying on the thirty days of Elul. Some also have the practice to read "Tikunei Ha-Zohar," a collection of inspirational passages from the Zohar (the basic text of Kabbala). The Kabbalists taught that the reading of this work has the capacity to cleanse and purify one's soul even if he does not understand the material he reads.
One must be particularly diligent during the month of Elul to recite each night "Keri'at Shema Al Ha'mita" before he goes to sleep. He should include the "Ana" prayer, petitioning God for forgiveness for whatever wrongs he may have committed over the course of that day.
One of the Berachot in the Amida service is that of "Hashivenu," in which we ask God to help us perform Teshuva. During the month of Elul, it is proper to insert in this blessing the names of people who have strayed from the proper path of observance, before the concluding blessing "Baruch Ata Hashem Ha'rotzeh Be'tshuva."
Many people have the custom to have their Tefillin and Mezuzot checked during the month of Elul. According to strict Halacha, a person is required to have his Mezuzot checked only twice in seven years, and Tefillin worn every day do not require checking at all. Nevertheless, there are those who make a point of having their Tefillin and Mezuzot checked during Elul.
Although one must ensure to recite Birkat Ha'levana (the blessing over the moon) every month, the Rabbis admonish us to be particularly diligent with regard to Birkat Ha'levana for the month of Elul.
In general, one must raise his level of observance during the month of Elul in preparation for the High Holidays, and in the merit of our efforts we should be deserving of a year of peace and happiness for ourselves, our families and our community, Amen.