Not sure what you mean by phonetic chart, but just thought I'd say that spelling in English isn't very logical. English has so many influences from other languages (and due to this, lots of non-English sounds that are now considered English) that it becomes an almost impossible task trying to pronounce new words. It's a lot of trial and error and unfortunately you'll just have to learn exception after exception after exception.
Sorry I can't help you further, but even natives have trouble saying new words correctly.