No, I don’t mean you should read your paper at a conference, that’s just too boring to listen to (so even if you have something interesting to say, we might not be paying attention). You should read your manuscript aloud before submitting it to a journal (or an abstract before you submit it to a conference). Reading aloud is quite useful to check the manuscript because doing so slows you down: you read it more carefully — and you might spot things you want to change.