One thing I see many sites do very bad is pick their social media icons. I like using interactive social media buttons, like I have in the sidebar you can see. But obviously some sites would rather use icons to save space or what not. However one thing I notice a lot is how ugly the social media icons they choose are. I've even seen sites use social media icons which have no design consistency at all, different sizes and random colours.
This icon set has a consistent minimal look across all the icons. The icons you use can give off an image of professionalism or amateurism - choose wisely.