"A good name is better than fine perfume". This is a statement that shows us it is important to build a good reputation. This is not to be done with manipulation or "people-pleasing". Rather this should be done with a life-well lived. If you consider what the Bible teaches us that a Christian is to be: loving, faithful, honest, compassionate, righteous, hard-working then we should have no problem building a good reputation if we simply obey God's Word. In essence, we don't have to figure out how we should live, but rather we must simply follow the instructions God has laid out for us in the book. If we do it well our reputation will take care of itself for most people. If we get the Great Commandment increasingly correct in our lives, then the love we have for God, and the love have for people will make a good name for us- to God's glory.
However, there is also an understanding that people who may speak against us do so for unfair reasons. Look at the life of Jesus. He lived perfectly, loved perfectly, and served perfectly. Yet, there were people who found something wrong in ever good thing that he did. Verse 21 is a good piece of advice. Don't worry or pay much attention to what everyone else says about you. Focus more on living the right way. If someone has a loving critique, then by my all means learn and grow. But if someone is just being nasty or is opposed to you for doing what is Biblically right then don't give it a second thought. Even Jesus had critics. He simply did not let the critics steer him from what was right or get him of track. We need that same attitude. At the end of the day, it is our reputation with God that matters. But I truly believe that by and large when we are right with God and living rightly according to God others will take notice- some will criticize, but many more will appreciate the life the faithful Christian man or woman leads.
Remember this: “We only have one life and it will soon pass. Only what’s done for Christ will last.” (CT Studd)