Eight weeks out, book the confession and check the passport. The State Department notes that some European countries require at least six more months of validity beyond the travel dates, and routine passport processing plus mailing can take two months, so a renewal started now may not arrive in time without expedited service. Enroll in the Smart Traveler Enrollment Program for embassy alerts, and read the travel advisory for the destination, especially for the Holy Land.
Six weeks out, start walking. Three or four outings a week of two to three miles in the actual shoes will show whether the shoes work before Rome's cobblestones do. Buy travel medical insurance with evacuation coverage; the State Department reminds travelers that Medicare does not cover care outside the United States. Fill prescriptions for the full trip plus a few days and carry copies of the prescriptions.
Four weeks out, settle the spiritual plan. An intention written on a card and carried through the pilgrimage keeps the purpose clear. If the pilgrimage includes a Jubilee or a Holy Door, the Apostolic Penitentiary's conditions for a plenary indulgence are confession, Communion, prayer for the Pope's intentions, and detachment from sin, which may fall within roughly twenty days before or after the visit; confession before departure can be part of that. The existing page on preparing spiritually suggests reading by destination.
Two weeks out, pack from the existing packing list guide, photocopy the passport, and tell the bank about foreign card use. The last week is for rest, not errands.