Complimenting others is like complimenting yourself. You make others happy and you make yourself happy too. It really doesn't matter how small the compliment is, just the intention and try speaks a lot about yourself.
A little "Wow, You look amazing today" will surely gain you more friends and people will start to like you and take you more seriously. It also depends in the manner you compliment people. You have to do it in a respectful manner, so as to achieve what you are saying.
Everyone should practise complimenting at work and off work. You never know when you will make someone's day with your compliments.