The fact is, communication is the key to any successful relationship. In new or "pre-relationships" however, non-verbal methods of communication are far more important than content. Simply put: it's not what you say, but how you say it. Think about it, you're in a social situation where you see someone you're attracted to - what do we do? It's rare that we immediately go up and introduce ourselves right away; we might look over, to see if a look can be exchanged, in order to help us gauge their interest. Even when we begin to talk to someone, we're usually engaging in small talk while trying to "figure out" their level of interest. Where things can get confusing, is when we try to decipher someone's personal body language code. There's a lot going on in the moment - our senses can be on overload when we're in the presence of someone we're attracted to, and it's easy to misread what they're "saying"...
Non-Verbal Communication and What it Means
1. Eye Contact. They say the eyes are the window to the soul - and it's true - you can get a lot of information about someone from what they do with their eyes. Good eye contact is a sign that someone is showing a certain comfort level. This could be an inherent comfort with themselves, that they're able to engage eye contact regardless of whom they're talking to, but it can also be a good indicator of interest in you. If someone is avoiding eye contact, it usually means one of two things - they're not interested, or they're very shy. Eye contact alone is not enough to determine whether or not someone is interested, but it's a good first indicator.
2. Restlessness. This is one of the more annoying, but very telling types of non-verbal communication. When someone is shifting in their chair, looking around, looking at their watch etc., they are telling you their mind is somewhere else, and that other things are more important than being with you. In a new or pre-relationship, there's really no excuse for this behaviour, and it means exactly what it feels like - they're not really interested.
3. Closed/Open Body Posture. This is a very strong indicator of where the other person is at. If someone has crossed their arms or turned their body away from you and appears quite stiff, it doesn't look good. You are literally seeing a physical representation of their emotions written all over their body - they're not open to interacting with you. They may be saying things that appear to sound pleasant, but usually that's just politeness to avoid the awkwardness of having to say they're not interested. Alternatively, if someone's facing towards you with "open arms", it's a good sign that they'd like to keep engaging.
4. Noticeably quiet. This can be an indicator of shyness, so you probably need to use other indicators to help you decipher the situation. If this is a first meeting, pay attention to how they interact with others - are they just as quiet? If not, silence can certainly speak more loudly than any words - it may be time to cut your losses. If someone is being quiet on a date and you haven't had this problem before, then something is definitely off. They could be having a bad day, or they might just not be interested anymore - either way, it is something that needs to be addressed.
5. Physical contact. This is often the biggest "go ahead" signal given. If someone lightly touches your arm or brushes against you, (and make sure it's not just a one-time accident), they are inviting you into their personal space. Do be aware that some people flirting even with people they're not necessarily interested in, and are quite "touchy-feely". Pay attention to how they interact with others to figure out if it's their general behaviour or if it's actually directed towards you. If you are dating someone who begins to exhibit changes in their physical contact (no longer holding your hand, taking your arm, being "late", being "too busy" - these are all good indicators that their feelings have changed towards you. These changes should be addressed.
It would be great if we could all be completely clear with each other about our intentions, but human beings are subtle creatures with real emotions. Reading people does come naturally for some, but for others it takes practise like anything in life, but it's probably one of the most valuable skills you can learn, and will help you in every situation, whether it be work or inter-personal relationships.