In Nichiren Daishonin's Buddhism, Gongyo means to recite the "Expedient Means" or "Hoben" (2nd) chapter and "The Life Span of the Thus Come One" or "Juryo" (16th) chapter of the Lotus Sutra in front of the Gohonzon. This is the supporting practice of all Nichiren Buddhists and is performed together with the chanting of Nam-myoho-renge-kyo, every morning and evening.
Format for Practicing Nichiren Daishonin's Buddhism: Sitting in front of the Gohonzon, so that it is in perfect view, one rings a bell and chants prolonged daimoku followed by Nam-Myoho-Renge-Kyo three times to commence Gongyo. The speed of the recitation will be that of a 'galloping horse'.
If it is morning, one faces east and chants daimoku three more times and then offers the first prayer 'Appreciation for Life's Protective Forces(shoten zenjin)'. In certain countries, all five prayers are recited at the end of gongyo.
One then rings the bell and recites the Expedient Means chapter. Another fact to note, is that if one is chanting with a group, only the leader of the prayer will recite the title of the chapter.
Next, one rings the bell again and recites the Life Span chapter. Upon finishing the recitation, one rings the bell while commencing the repetitive chanting of daimoku for as long as one wishes. There is no rule as to how long one must chant daimoku during gongyo. Some chant for a few moments, some for up to an hour or even longer. One can usually tell when the level of satisfaction is reached in their daimoku as each individual is different.
When one feels enough daimoku has been chanted, one rings the bell and chants daimoku three more times.
One then offers the second prayer, Appreciation for the Gohonzon, the third prayer, Appreciation for Nichiren Daishonin, Nikko Shonin and Nichimoku Shonin, the fourth prayer, for the attainment of Kosen-rufu and the Bodhisattvas of the Earth, and Personal Prayers, and the fifth prayer, Prayer for the Deceased (while ringing the bell continuously) and prayer for the impartial benefits of Nam Myoho Renge Kyo to spread to all beings in the universe and to raise the life condition of every one on the Earth..
One chants three daimoku upon the end of each prayer and prolonged daimoku at the end of gongyo.
In the evening, one does not offer the first prayer, but goes directly to the second, third and fifth prayers along with daimoku.
Sentient beings are innumerable; I vow to save them all.
Our evil desires are inexhaustible; I vow to quench them all.
The Buddha's teachings are immeasurable; I vow to study them all.
The way of the Buddha is unexcelled; I vow to attain the path sublime.
Ch. 2 (Hoben-pon) and Ch. 16 (Juryo-hon) are recited the most frequently; however, you may recite Ch. 12 Daibadatta-hon, whole Ch. 16, Ch. 21 Jinriki-hon (whole or from "Shobukkusesha") or Ch. 25 Kannon-gyo. Furthermore, it is a great practice to recite the whole Lotus Sutra from the beginning little by little everyday. You may choose which chapter to read by yourself.
In Nichiren Shu, Recitation of the Lotus Sutra can be performed in Japanese or your own language.
The sutra recitation is done in the Japanese pronunciation of Myōhō-Renge-Kyō, the Chinese translation of the Lotus Sutra by Kumarajiva. The number of recitations depends on which silent prayer is to be offered. The established format consist of five in the morning and three in the evening, with the Expedient Means and Life Span of the Tathagata chapters recited once for each silent prayer offered. The full Life Span of the Tathagata Chapter is recited only for the second prayer (an expression of appreciation to the Dai-Gohonzon); for all others, only the "verse" portion is recited. Each recitation of the sutra passages is followed three "prolonged daimoku" (hiki-daimoku, wherein each syllable pronounced distinctly and drawn out: "Na-Mu, Myō-Hō–Ren-Ge–Kyō–") and the corresponding silent prayer, except for the final recitation of the service, which is followed by the chanting of 100 or more daimoku and the final silent prayer. Note that the number of or the length of time daimoku is chanted between the final sutra recitation and silent prayer, is discretionary
Variations on this basic gongyo format, consisting of different combinations of the Expedient Means Chapter and parts of the Life Span of the Tathagata Chapter, are also offered on certain occasions, such as at mid-day meetings, before chanting daimoku for extended periods, and at funerals and celebrations.
The most important gongyo service in Nichiren Shoshu is the Ushitora Gongyo performed daily by the high priest or his proxy (when he is unable to officiate). Ushitora Gongyo takes place in the Grand Reception Hall of Head Temple Taisekiji and follows the format of the five-prayer morning gongyo service. It is done between the eponymous hours of the ox (ushi, 02:00) and the tiger (tora, 04:00), usually starting at 02:30 and taking about 50 minutes. Its purpose is to pray for the worldwide propagation of Nichiren Shoshu Buddhism and—by extension—the peace and prosperity of all the world's peoples
The significance of performing Ushitora Gongyo at this time of day derives from earlier Buddhist teachings that describe the hour of the ox as "the end of darkness" and the hour of the tiger as "the beginning of light," and ones that describe all Buddhas as having attained enlightenment at this time. The passage from the hour of the ox to the hour of the tiger therefore symbolizes the transition from the unenlightened condition of a common mortal to the enlightened condition of a Buddha, so the performance of gongyo at this hour as serves as a reminder of the true purpose of Buddhist practice: to achieve enlightenment in this lifetime.
Though in principle Nichiren Shoshu clergy and lay practitioners alike perform gongyo following the three-prayer–five-prayer format passed down through the ages at Head Temple Taisekiji, sometimes people under schedule pressure perform shorter variations while increasing the amount of daimoku they offer. This is because chanting as much daimoku as possible is the main practice of the Nichiren Shoshu faithful, whereas the sutra recitations are an auxiliary practice. Further, when circumstances prevent someone from performing gongyo according to established convention, it is better to do a shortened version and chant lots of daimoku than to lose daily contact with the Gohonzon.
The concept of gongyō is also common in Japanese Pure Land Buddhist schools such as Jodo Shu and Jodo Shinshu. The central practice of these schools is the recitation of the name of Amida, also called the nembutsu, but in daily practice a Pure Land practitioner will also chant excerpts of the Larger Sutra of Immeasurable Life, particular the sections titled the Sanbutsuge or the Juseige, and in some temples chanting the entire Smaller Sutra of Immeasurable Life may occur once daily or alternatively only on more formal occasions.
In larger Pure Land temples, the daily service is performed by priests or ministers, and lay people can optionally attend and recite along if they wish. The times for these services will vary depending on the individual branch, and individual temple.
In traditional Jodo Shinshu Buddhism, practitioners may also chant a hymn written by Shinran called the Shoshinge, which is not a sutra per se, but expounds the lineage with which Jodo Shinshu owes its beliefs. A shorter hymn called the Junirai, the Twelve Praises of Amida, can be used as well.
Further information regarding Pure Land daily devotions can be found here