Saint Louis de Montfort (1673-1716) did not want the consecration made lightly, so he laid out a period of preparation: twelve days spent emptying oneself of the spirit of the world, then three weeks devoted in turn to knowing oneself, knowing Mary and knowing Jesus Christ. Thirty-three days honour the years of Our Lord's earthly life. Each day takes about twenty minutes of prayer and reading; the point is not to complete a syllabus but to arrive at the feast day free, humble and in love. Saint John Paul II, whose motto Totus tuus came from de Montfort, described the reading of True Devotion as 'a decisive turning point' in his life.

What you need

• True Devotion to the Blessed Virgin by Saint Louis de Montfort, or a preparation book based on it
• A Bible and, if you have one, The Imitation of Christ, which the traditional readings draw on
• The date of the Marian feast you will consecrate yourself on
• About twenty minutes a day for 33 days
• A rosary

When to pray it

Begin 33 days before the feast so that the last day falls on its eve. Traditional starting dates: 9 January for Our Lady of Lourdes (11 February); 20 February for the Annunciation (25 March; 21 February in a leap year); 10 April for Our Lady of Fatima (13 May); 13 July for the Assumption (15 August); 4 September for Our Lady of the Rosary (7 October); 5 November for the Immaculate Conception (8 December); 9 November for Our Lady of Guadalupe (12 December).

Steps

1. 1

   Step 1: Choose the feast and count back 33 days

   Decide which feast of Our Lady you will make the consecration on, then count back so that the preparation begins 33 days before it and ends on its eve; the act is prayed on the feast itself. Write the dates of each stage in your calendar: days 1-12, then the three weeks of seven days each.

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   Step 2: Days 1-12: renouncing the spirit of the world

   The preliminary period is a turning away from what de Montfort calls the spirit of the world — pride, self-seeking, the love of comfort and applause — which is the opposite of the spirit of Christ. Each day read a short passage (the traditional readings come from the Gospels, especially the Sermon on the Mount, and from The Imitation of Christ), examine one attachment honestly, and pray the Veni Creator Spiritus▾, the Magnificat▾ and a Glory Be▾. An examination of conscience during these days prepares the confession you will make before the feast.

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   Step 3: Week 1 (days 13-19): knowledge of self

   The first week asks for humility: to know ourselves as we are, our weakness and our need of grace, without either despair or excuse. Read Gospel scenes of repentance and de Montfort's passages on our need of Mary, examine your conscience gently each day, and add the Litany of the Blessed Virgin Mary▾ to the daily prayers. Ask the Holy Spirit for self-knowledge that leads to trust rather than discouragement.

4. 4

   Step 4: Week 2 (days 20-26): knowledge of the Blessed Virgin

   The second week is spent coming to know Mary: her place in God's plan, her virtues, and her role as Mother of the Church. Read the Gospel passages where she appears (Luke 1-2, John 2 and 19) and de Montfort's chapters on true devotion, and pray the Rosary each day — the whole five decades if you can. Keep the Litany of the Blessed Virgin Mary▾ and the Magnificat▾ in the daily prayers. Saint Paul VI's Marialis Cultus is a sound guide here: authentic devotion to Mary is Trinitarian, Christ-centred, rooted in Scripture and the liturgy, and free of sentimentality.

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   Step 5: Week 3 (days 27-33): knowledge of Jesus Christ

   The final week turns to Jesus himself, to whom the whole consecration is directed: his Incarnation, his Passion, his Eucharist, his kingship. Read from the Gospels and from de Montfort on Jesus as the final end of devotion to Mary, keep the daily Rosary and Litany, and add the Anima Christi▾ or a prayer before a crucifix. The last day, the eve of the feast, is for quiet and for reading through the act you will pray tomorrow.

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   Step 6: Go to confession and receive Holy Communion on the feast

   Go to confession during the last week or on the eve of the feast. On the feast day attend Mass and receive Holy Communion. De Montfort intends the act to be made in the state of grace and united to Christ in the Eucharist, since the consecration is to him, through Mary.

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   Step 7: Pray the act of consecration

   After Communion, or before an image of Our Lady, pray the Act of Consecration to Jesus Christ through Mary of Saint Louis de Montfort slowly and in full. Many sign and date a written copy. Finish with the Magnificat▾ and the Memorare▾, and let the rest of the day be a celebration.

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   Step 8: Renew it each year

   Mark the feast in next year's calendar and renew the act on it, with the full preparation or a shorter one such as a novena. In between, renew it daily in the short form: "I am all thine, and all that I have is thine, O most loving Jesus, through Mary, thy most holy Mother." Living the consecration is the daily Rosary, the Angelus, and the habit of doing everything with Mary and for Jesus.

Tips

• A missed day is not a failure; simply continue where you left off. The dates are a help, not a law.
• Keep the daily prayers short enough to say every day; consistency matters more than volume.
• Make notes: a line each day on what struck you will be the best preparation for the act itself.
• Praying the schedule with a group — a parish, a family, a few friends — is the traditional way, and it makes the feast a shared celebration.