Saint Margaret Mary Alacoque - Feast Day is October 17th
St. Teresa of Avila - Feast Day is October 15th
St. Jerome - Feast Day is September 30th
A short of list of MUST knows...
St. Ignatius of Loyola - Feast Day is July 31st
St. Anne - Feast Day is July 26th
St. Bonaventure - Feast Day is July 14th
St. Aloysius Gonzaga - Feast Day is Jun 21st
St. Paschal Baylon - Feast Day is May 17th
St. Anselm - Feast day is April 21st
St. Andrew - Feast Day is November 30th
St. John of the Cross - Feast Day is November 24th