The Eight Hour Novena to The Holy Infant Jesus of Prague is said at approximately the same time every hour until the novena is finished. (The prayer is said nine times during the eight hours.)
Information on the history of the devotion of the Nine Tuesdays Novena in honour of Saint Anthony is located at:
http://missionbell.homestead.com/anthonycustoms.html
The 54 Day Rosary Novena: In this novena the Rosary is said for 54 consecutive days i.e. 3 novenas in petition (27 days) and 3 novenas in thanksgiving (27 days). The 54 day Rosary Novena was revealed by Our Lady herself.
All of these novenas receive marvelous results. If you choose any of them, please also pray for the Holy Souls in Purgatory and help them, and ask them to obtain the favours that you need. Saint Catherine of Bologna assured her sisters that: she obtained many favours by the prayers of the Holy Souls in Purgatory, which she had asked for in vain, through the intercession of the saints. Saint Theresa affirms that she always obtained the favours which she asked from God, through the intercession of the Poor Souls.
The following link has accounts of favours granted through the intercession of the Holy Souls in Purgatory for their benefactors and ways in which we can help the Holy Souls in Purgatory.
http://missionbell.homestead.com/Afavourgrantedbytheholysouls.html
It is important when making a novena to be in a state of grace, to have faith that God will help you, and to persevere in the prayer. It is recommended that you give a donation to a charitable organisation: such as the Saint Vincent de Paul Society.
The Memorare
Remember O most loving Virgin Mary that never was it known in any age that anyone who fled to your protection, implored your help or sought your intercession was left unaided, inspired by this confidence, therefore I fly to thee O Virgin of Virgins my Mother, to you do I come, before you I stand sinful and sorrowful, do not O Mother of the Word Incarnate despise my prayers but in thy mercy graciously hear and answer them. Amen.