Today the Roman rites dons the violet of penance and keeps a Vigil for tomorrow's feast of SS Simon and Jude.
The rite is simple. Mattins has three, proper, lessons. The second scheme of Lauds is used, the penitential form and, incidentally the old pre-1911 ferial Lauds in part. The ferial preces are sung, kneeling at Lauds and all the Hours. At Lauds the Suffrage of the Saints is sung.
Four candles are placed on the altar. At Mass the deacon and sub-deacon wear violet dalmatic and tunicle. The chant for the Mass is ferial, the second collect is Concede nos, and the third for the Church or pope. As there is no Gloria , following the usual rule, Benedicamus Domino is the dismissal.
In the afternoon first Vespers of the Holy Apostles SS Simon and Jude are sung, the altar has six candlesticks and the Hebdomadarius is assisted by four assistants in red copes. Compine is festal.
In the 'liturgical books of 1962' there is no Vigil just a IV class 'green' ferial day with the Mass of the previous Sunday without Gloria but with Ite. Mattins and the Hours are completely different and Vespers and Compline are ferial.