It seems natural to do more than one task at a time, however the brain does not like to do that. The brain handles tasks sequentially and can switch attention between tasks so quickly that we are given the illusion that we can perform multiple tasks together. Therefore, if you want to get more done using less effort, aim to work on what is called your attentional ability: focus and concentrate on one sequence - one task - at a time and avoid distractions. When you try to mentally multitask, you slow down your thinking and everything takes longer to accomplish. The brain loves the rhythm of sequences!