The simplest way to explain it is, Advent is a time of anticipation for Christ’s birth in the season leading up to Christmas. But that is only part of it. The word “Advent” is derived from the Latin word adventus, which means “coming.” In the Greek translation, this means parousia.
Scholars believe that during the 4th and 5th centuries, Advent was a season of ‘preparation’ for the baptism of new Christian’s at the January feast of Epiphany, the celebration of God’s incarnation represented by the visit of the Magi to baby Jesus (Matthew 2:1), His baptism in the Jordan River by John the Baptist (John 1:29), and His first miracle at Cana (John 2:1). During this season of preparation, Christian’s would spend 40 days in penance, prayer, and fasting to prepare for the celebration. By the 6th century, Roman Christians had tied Advent to the coming of Christ. The “coming” they had in mind was not Christ’s first coming … but His second coming as the Judge of the world (see Revelation). It was not until the Middle Ages when the Advent season was explicitly linked to Christ’s first coming … Christmas. 

O come, O come, Emmanuel,
And ransom captive Israel,
That mourns in lonely exile here
Until the Son of God appears.
Rejoice! Rejoice!
Emmanuel shall come to thee, O Israel.

Advent readings are broken down for each Sunday of Advent:
1) Hope (or promise)
2) Preparation (waiting or prophecy)
3) Joy (peace)
4) Love (adoration)
Prayer is a wonderful and most powerful way to open your heart and prepare for the joy and hope of Christ’s birth. Here is a sample prayer to use during the season to focus your heart and mind on the birth of Jesus Christ our Savior. Read more

The St. Andrew Christmas novena is traditionally recited 15 times per day starting on November 30th and going through Christmas Day on December 25th.