Whether it takes 7 seconds or 17 minutes to make a first impression, people always seem astonished at what idiosyncrasy causes the gut reaction.

Recruiters know this: That reaction may be positive or negative, but it pays to know how others perceive you.

After more than 30 years of personal coaching and studying the topics of interpersonal skills, body language, interviewing, and career advancement, these issues are mentioned most frequently as those that make someone memorable — typically for negative reasons.

Of course, there’s always the outlier — the person who interprets the habit or trait positively.

So to be complete, I’ve listed both potential reactions or the first impression below — the positive and the negative. Take your pick:

1 – The “EST” Habit

Routinely “top” every comment someone else makes with one of your own. You have the “best” job, the “funniest” story, the “fastest laptop,” the “easiest” process for managing remote contractors.

  • The positive reaction: The most competent person in the room.
  • The negative reaction: A blowhard — typically bragging without reason.

2 – Limp Body Language

Sauntering walk. Slumped shoulders. Small, limp gestures. Blank facial expression.

  • Positive reaction: Non-threatening or intimidating.
  • Negative reaction: Low energy. Slow (physically and mentally). Low self-esteem.

3 – Boisterous laughter

Habitually loud, unrestrained laughter at almost any happening except for the gravest situation.

  • Positive reaction: Jovial, pleasant person.
  • Negative reaction: Moronic behavior; trying to attract attention and knows no better way to do it.

4 – Entering a room flamboyantly

Arrives noisily in such a way that your entrance immediately attracts attention — with loud greetings, an entourage of people or things accompanying you, or extraordinarily late with profuse apologies to everyone.

  • Positive reaction: Must be a confident, take-charge person.
  • Negative reaction: A very self-absorbed, insincere person

5 – Verbosity

Talking incessantly about whatever topic is at hand — whether adding substantive or trivial comments.

  • Positive reaction: Entertaining.
  • Negative reaction: Nervous; can’t figure out what’s important and what’s not. First impression is boring.

6 – Nodding continually as others speak

Does it in meetings, in conversations, during lectures.

  • Positive reaction: A pleasant, agreeable person.
  • Negative reaction: Doesn’t this person have any opinions or ideas of their own?

7 – Writing in fragmented spurts

Writes emails that read like stream-of-consciousness thoughts — sentence fragments, missing details — that leave readers guessing at what’s “between the lines.”

  • Positive reaction: Must be a terribly busy person forced into an unfocused situation.
  • Negative reaction: They must be illiterate.

8 – Overpowering handshake

Either crushing the other person’s hand in a painful grip, or, maneuvering the handclasp so that your own hand is always on top.

  • Positive reaction: Powerful person.
  • Negative reaction: A manipulator; trying to impress.

9 – Jewelry

Wears odd jewelry that distracts rather than compliments personal assets and clothing.

  • Positive reaction: A risk-taker.
  • Negative reaction: Big attention-seeker, a rebel.

10 – Improper grammar

Subject-verb disagreement. Misused words. Awkward sentence construction.

  • Positive reaction: Obviously speaks multiple languages, and this is not his or her native tongue.
  • Negative reaction: Uneducated, native speaker of the language. Why is he or she unwilling to learn?

Dianna Booher

Dianna Booher is CEO of the Booher Research Institute and founder of Booher Consultants, Inc, which is now part of Communispond. She's a prolific author of 47 books, published in 60 foreign-language editions. She's a prolific author of 47 books, published in 60 foreign-language editions, and a well-known speaker on leadership and leadership communication. Her latest books include Communicate Like a Leader: Connecting Strategically to Coach, Inspire, and Get Things DoneWhat MORE Can I Say? Why Communication Fails and What to Do About ItCreating Personal Presence: Look, Talk, Think, and Act Like a Leader; and Communicate with Confidence. She helps organizations to communicate clearly and individuals to increase their influence by a strong executive presence. Her clients include IBM, Lockheed Martin, JP Morgan Chase, AMR, PepsiCo, Frito-Lay, Brinker International, Chevron, BP, and the United States Navy, to name a few. You can follow Dianna on Twitter @DiannaBooher, or connect with her on LinkedIn.