Practice practice practice. I think 4 to 5 books is even an excessive reading exercise without some good amount of practising. Best way to do this, I believe, is to start refactoring your current projects using the patterns. Or if you don't have any projects you're actively working on then just do it your own way and then try refactoring to patterns.
You cannot appreciate them fully if you haven't suffered through the problems they solve. And please keep in mind that they are not silver bullets - you don't need to memorize them and push it hard to apply on the fly. My two cents..
