OMG ENOUGH ALREADY!!!
I am gonna have to call the Pope and tell him to get in his Pope-mobile (that bubble car,) and round all of you up and answer your 11.5 TRILLION questions about saints. Goodness gracious, knowing Hoodoo or a Catholic background does NOT make me an expert on every Catholic saint, and for the love of all things holy, no, I do not know what colors, foods, or etc Saint Zephyrinus likes.
First of all, calm yourself.
Now, let me impart a great piece of wisdom upon you - usually, if you want the help of a saint - ANY SAINT, - all you have to do is pray to that saint. That's it. That's all you need.
Okay, I see someone foaming at the mouth in the back of the rant room giving me drama about how this saint requires publication of thanks and that one likes red candles, and, etc. I see you missed the "MOST OF THE TIME" mentioned in the previous paragraph.
Want to know the basic way to petition a saint? The "classic" way if you will? Okay...get yourself a statue or holy card of the saint you wish to petition. Get a white candle. Get a glass (generally a tumbler) and fill this with water. Place the water next to your picture or statue of saint. Light your white candle and place this near your picture or statue of saint. Say prayer.
What next? You are going to repeat a same set of actions for a prescribed number of days, depending on how many days you are praying. For example... If you're saying a novena (a nine-day prayer,) you should allow the candle to burn out (assuming its a one day candle,) and then light a fresh one the next day, replace the water and say your prayer...so every day for nine days you burn a candle, replace the water and say your prayer.
What if you use a seven-day candle? In this case, I usually say the prayer once each day while the candle is burning. Some people say the prayer once, but I guess that is just their preference. I personally feel that repeating the prayer every day is going to bring a better result, but I leave the decision up to you.
How do you know what color is best? Listen, if you have no idea of what color to use, white will work. Not all saints have "preferred colors." Sometimes, but not always, the prescribed color is one that you are given to reflect the need, sometimes, but again not always, sometimes the specified colors in ATR's are what they are because the Saint is being parallelled to reflect a Traditional African Religious spirit, or even to another godhead, or other cultural spirit. Sometimes, but not always, it is just a color that the saint "prefers."
What if the saint has special specifications, needs, etc? Um, well, the short list I know is....I've always heard that St Expedite, St Jude, and St. Theresa all want their names published, but St Expedite can be given a piece of poundcake or flowers instead or as well. I have also heard that St Rita likes a published thanks, but I can't confirm that other than having heard it.
I have heard repeatedly that St Anthony likes brown candles, cigars and rum.
St Rita is said not to like men. St Martha is said by some not to like working with men. I have heard St.s Peter and Luke do not like working with women. I am not so sure on the Luke, but I've heard that St Peter doesn't like working with women more than once. Santisma Muerte HATES adulterers. If you've committed adultery EVER, or are the "other party" of an adulterous relationship, I don't recommend seeking her help - but if you're a woman with a cheating husband, she will usually gladly be of assistance. She also often is best petitioned by women.
You know if you want to make an offering, flowers are always good - or even better, donate in the saint's name to a charity, especially one that is related to the saint's patronage.
If you need to find who is the patron of what Wikipedia and Catholic.org should help you.
You know, there is a lot to also be said for picking one or two saints and developing a relationship with the saint by praying to him/her most often. Just because a saint is a patron of a particular thing does not mean he or she cannot help on other problems outside of his or her patronage.
Hmmm.... That's what I can think of off of the top of my head. ;)