1. False/Misleading Claim - Never make false or misleading claims about your brand. It's the easiest way ruin the reputation of your brand. The "fake it to you make" logic should never apply to your brand.
2. Distracted Social Media Accounts - Each social network serves a specific purpose in branding. Use your social accounts appropriately while staying on message. If your brand is related to dental, talking about Kim Kardashian in general doesn't add value. (Unless you are talking about her teeth)
3. Poor Profile Images - every image you post represents your brand. Does this image make a good representation of my brand? Is this a good picture of me? Who is going to see these images? Images add lots of value to your brand, keep them in scope of your branding goals.