This is very important for people who are striving in the deen to comprehend. We will not approach Allah by removing the Sunnahs from our life . It has been the habit of the pious predecessors before us and the pious that will come after us to seek out every Sunnah that they can find..
The command of Allah is "Ateeullah war rasool---Obey Allah and His Messenger". In this day and age, we have a classification of our legal system, so we say that "This act is fardh, this act is waajib, this act is sunnah muakkadah, this act is sunnah ghair muakkadah, this act is nafl, this act is mustahab.....etc etc.".
However, the Companions (radiyallahu anhum) didn't make any distinction between fardh and Sunnah. Whatever they saw the Prophet S.A.W do, they did and whatever he told them to do, they did. There was no distinction at that time that "Oh this is fardh and this is a Sunnah" If it came from Rasoolullah S.A.W it was to be done. Period. They made no distinctions.