Make eye contact.

When you first meet someone, always look them in the eye. A study by Northeastern University asked participants to watch videos of strangers talking to each other for the first time and rate how intelligent each person appeared. The people who consistently made eye contact while speaking were considered more intelligent than those who didn't.
Talk rapidly.

Speaking quickly makes you sound like you know what you're talking about. A study from Brigham Young University created 54 synthetic voices and asked participants to rate how competent each speaker sounded. The faster the voice, the more competent the speaker was rated.
Take out your piercings.

Research in the journal "European Psychologist" revealed a negative correlation between perceived intelligence and the number of facial piercings. Participants in the study were shown photos of male and female models, and rated those without any piercings as more attractive and intelligent.
Dress well.

Unsurprisingly, dressing well gives off a vibe of success and confidence. A 2011 study published in the journal "Psychology of Men & Masculinity" found that when participants compared photos of men in suits versus nontraditional business attire, they assumed the better-dressed men earned higher salaries and were more likely to be promoted.
Choose brand-name clothes.

According to a Tilburg University study, wearing expensive clothing automatically makes people perceive you as more successful. Study participants wearing "luxury brands," such as Lacoste, were more likely to get donations for a charity and convince people to fill out surveys as they passed by.

http://www.realentertainmentnaija.com/2014/07/5-strategic-ways-to-stay-competent.html