If you're not into taking hormones to prevent pregnancy, and you don't want something long-term like the Depo shot or an IUC, then condoms are a great option. If you're not a fan, another short-term option is to use spermicide, but I only recommend it if the person you're with is STI-free. Creams and gels can be really messy though (and some stain your sheets), so that's where VCF (vaginal contraceptive film) comes in handy! You insert it into your lady business 15 minutes before sex and it kills the sperm, preventing you from becoming preggers.
If you don't know much about it, take this quiz to get all sorts of info, and if you're intrigued and want to give it a try, the VCF website is offering free samples. Just fill in the form and they'll send you three individual films at no cost. It's a great way to give this uncommon form of birth control a try.