Check the Lent section of the Seasons page for resources to help with liturgy planning during Lent. The Season of Lent leaflet from the Liturgy Office is very useful as a starting point and source of background information.
“The annual observance of Lent is the special season for the ascent to the holy mountain of Easter. Through its twofold themes of repentance and baptism, the season of Lent disposes both the catechumens and the faithful to celebrate the paschal mystery. Catechumens are led to the sacraments of initiation by means of the rite of election, the scrutinies, and catechesis. The faithful, listening more intently to the word of God and devoting themselves to prayer, are prepared through a spirit of repentance to renew their baptismal promises.”
(Ceremonial of Bishops, 249)