An indulgence can either be partial or plenary. It is partial if it removes only part of the temporal punishment due to sin, or plenary if it removes all punishment.
To be able to gain an indulgence, one must have the intention to gain them, and perform the works at the time and in the manner prescribed.
To attain a plenary indulgence, three conditions must accompany the prescribed act:
1. The faithful must receive the sacrament of confession, either eight days before or after the pious act is performed.
2. Receive Holy Communion on that day.
3. Recite prayers for the intentions of the Holy Father (one Our Father and one Hail Mary is the minimum. but any other additional prayers may be added).
All attachment to sin, even venial sin, must be absent. If one's disposition is less than perfect or if some of the above conditions are not fulfilled, the indulgence becomes partial. One must also remember that only one plenary indulgence a day can be acquired.
Indulgenced Acts for the Poor Souls
A partial indulgence can be obtained by devoutly visiting a cemetery and praying for the departed, even if the prayer is only mental. One can gain a plenary indulgence visiting a cemetery each day between November 1 and November 8. These indulgences are applicable only to the Souls in Purgatory.
A plenary indulgence, again applicable only to the Souls in Purgatory, is also granted when the faithful piously visit a church or a public oratory on November 2. In visiting the church or oratory, it is required, that one Our Father and the Creed be recited.