Saturday is the day for Our Lady. One Saturday a month is the First Saturday devotion for her, and the current Roman Missal encourages priests to celebrate the Mass commemorating the Blessed Virgin Mary on Saturday.
Jesus’ day is usually Friday because of First Friday once a month and because of commemorating the Crucifixion on that day.
There used to be other days in the week that were especially for particular votive Masses. The Cross was on Friday, the Angels were on Thursday, and the Holy Spirit was Wednesday. To my knowledge that was done away with before Vatican II and now you can have a Mass of the Holy Spirit on any weekday as long as it doesn’t conflict with some other feast. One of the local priests likes to have Mass of the Holy Spirit so he had one on a weekday a couple weeks ago.
There have also been a couple of private revelations, one approved for faith expression and the other approved by the local bishop, in which St. Joseph is said to have appeared and asked for a First Wednesday devotion. Although this hasn’t caught on in USA yet, I was considering doing it because I generally go to Mass anyway and I think it’s very important to pray to St. Joseph.