Please give advice quickly!

I just got some olive oil and would like to deep condition my hair this weekend -- I'm seeing my fiance for the first time in over two months, so I want to look gorgeous! My hair's been a bit dry lately, and I would really like to remedy that. What's the best way to use olive oil? I know I should warm it, apply it, and leave my hair up in a bun for as long as possible with the oil on it... but should I apply it to wet or dry hair? Should I wash it out or simply rinse? Should I then condition? How often can I do this? (My hair can never be overconditioned.) HELP!!!