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The Tridentine to Novus Ordo "evolution" was a gradual process which occurred over a 7 year period. Some would argue that it began earlier than 1962, and some will contend that the process is still evolving to this day. But to answer you question in a general sense, the process occurred between 1962 and 1969, with the Novus Ordo being officially put in use on the First Sunday of Advent, 1969.

The changes came in three obvious rounds, with a few modification in between too.

The first round was enacted in 1964 by Pope Paul VI's "Inter Oecumenici", and put into effect Jan 1, 1965. This was what is commonly referred to as the 1965 Missal. Many, including myself, will argue that this Missal was the true reform called for by Vatican II and no further reforms were needed per the council. This was still the Tridentine Mass, but without Ps. 42 in the beginning and the Last Gospel and Leonine Prayers at the end. Also allowed was a limited use of the vernacular, with the core of the Mass always being in Latin (e.g. Offertory, Canon).

An interim change occurred in 1966 allowing the Preface to be in the vernacular.

In 1967, the document "Tres abhinc annos" ushered in the second round. Here more vernacular was allowed, and many genuflections and signs of the cross were eliminated on the part of the priest. The Roman Canon was now allowed in the vernacular, thereby allowing an entirely vernacular Mass for the first time. But, this was still the Tridentine Mass, just in the vernacular and somewhat bastardized.

In 1968, the three additional Eucharistic prayers were published and allowed for use.

Finally, in 1969, the last round happened. All prior reforms were discarded in favor of a newly drawn up Novus Ordo.

You may want to read Michael Davies's "Liturgical Revolution". Book 3 of the series, entitled "Pope Paul's New Mass" gives a very detailed and accurate expose of the general changes I listed above.