Really comes down to chemistry when we meet, doesn't it!
Do you value your health and fitness? Well educated (Bachelor's degree or higher)? Have a good job? Enjoy traveling, being active and outgoing? Have a good sense of humour?
Non smoker is a must, also I hope you're not into alcohol or drugs and its better if you're vegetarian/vegan.
Should be someone that doesn't take religion seriously and isn't judgmental. Looks create the first impression although for me there is much more to a person than just that.
At the end of the day, these are all just ideals and the chances that you're the perfect girl with all these features is quite low, so just say hi and lets see how it goes!