It all depends how long you know her.
If you just met her, you shouldn't really be too ****y with your comment. Remember, first impression is everything. If she tells you that right away, it shows some level of attraction. So, you should say something like: Thanks, I really like yours too!
Only say that if you want her. That comment will plant the seed. I always get comments from girls about my smile and saying that works great for me.
If you known her a while, but there is not that much connection between both of you. Then you could say something like: I bet you tell that to all the guys you meet!
Again, only say this if you want her. Don't give ugly women false hope (they tend to be clingers, and it feels horrible to tell them you don't like them.)
If there is a lot of trust between you too. You can go as ****y as you want. I will say something like: Yeah, I like them too.
Whenever I say something like that, I can see in their expression that they are thinking: you jerk! (they love it thou)
