This Saturday I am finishing up my 5th first Saturday for this devotion. If you can it would be good to go to confession but you have from what I understand 8 days before or 8 days afterward to go to confession. This is from the rosary center.org.
It consists in going to Confession, receiving Communion, reciting five decades of the Rosary and meditating for a quarter of an hour on the mysteries of the Rosary on the first Saturday of five consecutive months. The Confession may be made during the eight days preceding or following the first Saturday of each month, provided that Holy Communion be received in the state of grace. Should one forget to form the intention of making reparation to the Immaculate Heart of Mary, it may be formed at the next Confession, occasion to go to confession being taken at the first opportunity.
It means saying the rosary plus another 15 minutes. The 15 minutes is time spent in the company of the Blessed Mother meditating on Her Son. I have a rosary pamphlet on the mysteries and I usually read it and meditate on them.
DISCLAIMER: Catholic Answers has turned over the archive to Catholic-Questions.org and no longer owns, manages, or moderates the forums. For additional apologetics resources please visit www.catholic.com.