In wikipedia i found a list of methods of teaching foreign languages - language pedagogy. But it's seems that we not have a well recognized method or methods, or more effective then others, or at least teaching methods for which there a consensus among researchers? Can someone tell which theories (some points in theories) is predominant or more effective today, after i think 20 years of research in foreign language teaching? (Ex. Never translate words in L1, show images instead. Use IPA for teaching sounds of FL, never use the voice of teacher as an example. Memorize adverbs first, then interjections, only this order work for successful foreign language learning). So, can i find a list of well established theories or recommendations somewhere?
Everybody learns languages differently, depending on how they learned their own languages, how close the language they're learning is to them, what their motivations are, how hard they work, whether they're literate, whether they're intelligent, and a whole lot of other things.
Therefore, there can be no method of teaching that will work best. Some ways will work with some students when used by some teachers. Other combinations won't. You have to try a lot and see what works with which students.
As a consequence, you should realize that no theory about foreign language teaching methodology is authoritative; most textbooks believe they are better and say so, but there's no evidence.