We awaken to enlightenment by recognising and fully realising the primordially pure essence already present as our nature. That's how to be an awakened Buddha. Even though the enlightened state is actually already present, imagining or forming a thought construct of enlightenment doesn't make you enlightened.

It's the same as when you are really hungry and you look at a plate of food and try to imagine what it tastes like. Does it work to then imagine, "Mmmmm, I'm eating the food, I'm no longer hungry." You can think this for a very long time – forever, in fact – but it still doesn't dispel your hunger. Once you actually put the food in your mouth, it tastes delicious, and you are no longer hungry.

It's the same with experience. Experience only occurs in a direct way, in practical reality, not through a theory about taste. If your meditation practice is merely an exercise in imagining and keeping something in mind, it is only a theory and not a direct experience.

-- Tulku Urgyen Rinpoche