Ёлки-палки or Yolki palki - for expressing surprise, like Holy cow. I would do a double-take if any non-Russian speaker says it to me.
You can also try asking her what Бычить / Bycheet means. That would be an interesting conversation if she doesn't know English.
Some general compliments:
"Мне нравится твоя прическа / Mne nravitsya tvoya pricheska" is "I like your hairstyle"
"У тебя красивые глаза / U tebya krasivye glaza" is "Your eyes are pretty"
Cool Russian phrases... I'm not sure what to tell you here, like, what would you want to say? What do you...