I've personally said all of what is listed in this article and have freestyled my own moving on. Everyone loves to hear optimism and if they don't then it really isn't mentally healthy or attractive to be arround.

Try these and some of your own in all sorts of environments. You can start by practicing with yourself in the mirror. It can help with confidence in yourself when saying something genuine, subtle, yet not frequently used, and bland. Practice on your parents, random people in the grocery line, even the cute girl in your class or office.

Compliments can completely change the mood in a room while also opening for control of the room. I do this to my boss and coworkers regarding their work ethic whether it be via email or verbally.

Edit: Looks like I goobered up and pasted the link incorrectly. Now that I've misplaced the article here's one that's similar. http://get-a-wingman.com/how-to-compliment-a-woman-and-win-her-attention/