My understanding is that in these times it was not uncommon to observe many more holidays than are commonly observed in the west, various saint's feasts and religious holidays among others, what was it like to celebrate holidays for an average person?
Clarifying question: Because there were so many different holidays and feast days, and because the form of celebration differed so widely from place to place, and changed so much over time, do you have maybe one holiday in particular you're wondering about, or perhaps 2 or 3 key holidays you're interested in? Otherwise, your question as asked might take a whole series of books to answer! :)