When speed reading, it's important not to "say the words in your head." But speed reading isn't fun—you blaze through it so fast that you hardly get a chance to even understand the words, let alone enjoy them. Don't try to speed read unless you're being forced to read something boring and you just want to get it over with.

Find a speed which is comfortable for you. Speed up when you're feeling eager, slow down when you're going through a particularly good bit and you want to savour it. There's no one right speed for every context, much less one right speed for every reader.