Be genuine. Do not pretend to be someone you are not just to pique her interest. She will see right through this and immediately peg you as someone who cannot be trusted. To build the relationship, find common ground with her. Discuss shared interests and do more listening than talking.
Make appropriate eye contact. Men often make women feel uncomfortable with eye contact. If you are nervous, your natural tendency may be to look away or avoid eye contact. This makes you appear shifty and will cause her to question your motives. On the other hand, you might be unable to take your eyes off her. Even if you are innocently admiring how gorgeous she is, being stared down will make her feel like a piece of meat. Your moments of eye contact should be brief but frequent. In general, make more eye contact while listening, but a little less while talking.
Make your intentions clear from the get-go. If you are hoping she will be a one-night stand, don't lead her to believe that you are looking for a dating relationship. While you might successfully deceive her, it is unethical to lie to get what you want. On the other hand, if you are already in a relationship, be transparent about how serious you are. Don't lead her to believe that you foresee marriage when you are actually considering breaking up. On the flip side, don't tell her that you are happy with a casual relationship if you want to be exclusive.
Extend trust to her. If you show that you trust her, she will trust you. You can do this by revealing more of yourself or relying on her to fulfill promises she makes. Don't expect her to give you more trust than you have given her.
Avoid keeping secrets from her. If there is something that you have not told her and feel that it could impact the relationship, you should fess up. If you keep a secret that she finds out about later, she will lose any trust that has been cultivated.
Refrain from lying because it can destroy trust faster than nearly anything else.
Evaluate when to push for more intimacy and when to back off. At the beginning of a relationship, it is absolutely inappropriate to pry into a woman's deepest dreams and fears. Over time, you can have these conversations, but never push her beyond what she is comfortable with.
Make appropriate physical contact. Most women love hugs, and the physical closeness that they provide can encourage trust. A hug is a very safe way to move towards physical closeness and vulnerability. To maintain the trust that you have built in this area, be cautious about moving too far, too fast. Forcing an unwanted kiss or grab will cause her to pull away from you.