I celebrate all the Sabbats. If I am doing a solitary ceremony, I use generally accepted Neo-Pagan names for the fire festivals. For the solstices and equinoxes, I will usually call them Summer Solstice, Autumn Equinox, etc. Sometimes I will do a full or new moon ceremony.
I also do devotionals to particular deities but I don't time them to any specific calendar except for belonging to an online flame tending group for Brighid. I would actually like to do more of this with different deities even if I set up my own calendar.
Some of the secular holidays I will honor with my religion in mind just like those of other faiths. For example, since ancestor worship is a strong component of my path and there are a lot of war veterans in generations of my family, I will show reverence on Memorial Day to the ancestors and to gods of war and peace.