Facebook
- Don't brag about speeding tickets, criminal behavior or other acts of truancy
- Avoid photos of a messy apartment or dorm room, which could convey laziness.
- Watch for obnoxious comments from friends.
- Avoid poor grammar or text lingo.
- Be mindful of what people are doing in the background and foreground of photos before posting.
- Post photos and statuses that highlight volunteer work or accomplishments.
Twitter
- Write a strong bio/about me section.
- Share interesting news or content.
- Once something is on the web, it never goes away. Ask yourself, "Am I OK with this tweet being online forever?" before hitting "send."
- Retweet only relevant information. Don't retweet too often.
- Nobody cares what you had for lunch. Don't tweet meaningless info.
- Don't tweet negative comments about your job. This applies to Facebook statuses, too.
- Always ask, "Would I enjoy reading this if someone else wrote it?"
Source: Virallock
