Matt 5:16: Let your light so shine among men, that they may see your good works and glorify your Father which is in heaven.
This works in the context of us being representatives of our Father (2 Cor 5:20). As representatives (ambassadors, sent ones, messengers) everything we do reflects on the one who sent us and impacts the credibility of our message. Everything we do, we must therefore do it as though it is being done for the Lord because, in a sense, it is (Col 3:22-24).
This presupposes that we announce ourselves as followers of Jesus. This is an obvious presupposition since it is that very announcement that initiates us as a follower (Mark 16:16).