asking a coworker out: when were how?

so there's this girl a few years younger than me that i really like we have both been contracted to work with a company for 3months, im going to ask her out its just a matter of when and how, we get along really well and can enjoy a good laugh together. so option #1 ask her out now [8 weeks of contract left] option #2 wait till the last few days of contract. each option has its pros and cons ... opinions please