Here's the criteria for the indulgences:
The 3 constants for all indulgences:
1) Prayers for the intentions of the Holy Father (usually an Our Father, Hail Mary, and Glory Be)
2) Receive the Holy Eucharist.*
3) Make a good Confession. A Confession made up to a week before or a week after the 4th item applies.
And then there is the 4th criteria, which changes with each indulgence. The two I mentioned today as being connected to All Souls Day and Allhallowstide (the octave of All Saints, i.e. the First through the Eighth) are:
For Nov. 2nd only: A plenary indulgence, applicable only to the souls in Purgatory, may be obtained by those who, on All Souls Day, piously visit a church, public oratory, or (for those entitled to use it) a semi-public oratory. On visiting the church or oratory it is required that one Our Father and the Creed be recited for the dead.
For Nov. 1st-8th: Visit to a Cemetery. Applicable only to the souls in Purgatory when one devoutly visits and prays for the departed. A plenary indulgence is bestowed for this work each day between November 1 and November 8, inclusive.
* Note: Holy Communion follows the same "week before or after" rule that applies to Confession, except, if a person is seeking indulgences on multiple days, while they don't need multiple Confessions, they do need separate Communions. So if a person went to Confession on November 5th and visited cemeteries on Nov. 1st, 2nd, and 7th, they do need 3 Holy Communions (and prayers for the Holy Father, but those usually go with the "work"). As best as I can tell, the Communions don't have to be on the same days as the works, but probably follow the "week before or after" rule. But I don't think a separate Communion is called for if a person both visits a cemetery and a church on Nov. 2nd.
