Empty is certain condition of  one's mind.
In that stage, one try to not think anything just let the mind free, no bound up at all.It is not easy to do so.Most of us had used to busy,busy,rush to something without thinking what our busy for.
Empty give one's mind a chance to reduce the stress,release the negative thought,relax the body muscle.Then one can redeem, rebuild one's confidence,faith,strength,have a positive attitude to face the world.Throw away the guilty,jealous,anger,fear.....regret for past or worry, anxious for tomorrow.Focus on  what you really have now with light up mood and appreciation.
Those are empty do for me. I learn one of Yoga skill today.