The fact that Santería has been kept alive for hundreds of years via oral tradition is understandable in historical context - in Cuba, slaves could not read and write - but in practical terms, it means there's no "how to" manual for Santería. Someone who wants to know what "authentic Santería" is like, and who imagines that all knowledge about the religion can be written down, agreed upon, and put into practice the same way by millions of people around the world, well, this person will be bitterly disappointed. Looking for the single right way to do something in Santería is like looking for the pot of gold at the end of the rainbow. It always eludes us, because it doesn't really exist.
These sayings suggest that Santería views learning as a lifelong process, and one that's never fully complete. There are definitely rules about how things should be done, and learning to respect the rules is an important part of spiritual development. But, the only way you can learn what's right and what's wrong, what's expected and what's going to cause problems for you, is by listening to your godmother or godfather, learning how things are done in your particular lineage, and participating in religious activities with your community. The elders will teach you, poco a poco, what you need to know, when you're ready to know it. As the learner, you can't set the pace; the teacher sets it for you. However, most teachers are delighted to find students who want to learn and who are serious about the religion. In emotionally healthy communities, elders share their knowledge with younger Santeros/as to guarantee the knowledge isn't lost.
If you're not initiated and don't belong to a community of Santeros, what are you supposed to do? Fortunately, many skilled priests are writing about the religion now, both in book form and on the internet. Much more written information is available now than ever before, and there's less reluctance on the part of Santeros/as to share information with outsiders. My advice is to read a variety of sources and look for common threads, patterns, and general observations that seem to be repeated by multiple authors. Use your critical thinking skills to question the qualifications of the writer, the reliability of the information, and the author's motive for writing. Think about what you read, and keep an open mind. Use book learning to understand in theory what the religion is like, but don't forget that book learning has limits. Avoid writers who claim to possess the absolute and only truth, especially if they're arrogant and disrespectful of other people. After you've looked at some books and some internet sites, you'll start to get a sense of who gives reliable information and who doesn't. Trust your judgment, and let your head lead you in the direction you need to go in.
Here are two websites that provide reliable accurate information. The authors are experienced Santeros with a solid base of knowledge: