This question has probably generated more books, videos, seminars, blogs, apps, and heated debates in forums than almost any other end-user question. I’m sure you’ll get lots of good advice here – I won’t describe my own practices because whatever I do is no good for anyone else.
But I’d advise and suggest a good, hard, long think about what it is you’re trying to accomplish. Write it down, diagram it if pictures help. Then put it away for a week and come back to it.
Most likely everything you’ve tried has not worked for you because what you really want is not specified clearly and simply.