Here are 10 behaviours that can lead others to perceive someone as weird or socially awkward.

1. Eye Contact: Both too much and too little eye contact can be problematic. It's important to maintain a balance.

2. Personal Space: There are norms regarding personal space (about 12-18 inches in the U.S.) that must be respected.

3. Hygiene: Poor oral or general hygiene can lead to negative perceptions.

4. Lack of Filter: Speaking without regard for appropriateness, such as discussing taboo topics, can make one seem socially awkward.

5. Face Work: Not cooperating in saving face for oneself or others during interactions can contribute to the perception of being weird.

6. Self-Disclosure: Oversharing too soon or not sharing enough can both violate social norms.

7. Relevance: Contributions to conversations should be relevant; abrupt topic changes may seem strange.

8. Entering/Leaving Interactions: There are social rituals for how to gracefully enter and exit conversations.

9. Back-Channel Cues: Failing to provide cues that indicate listening can be perceived as disinterest or awkwardness.

10. Empathy: A lack of empathy can lead to misunderstandings and social isolation, as it prevents recognising and responding to others' feelings.