We sometimes avoid the poses that we think we just can't do, the poses that maybe our bodies weren't "built" for. Hanumanasana is just one of those poses. Full splits are something we feel we either can or can't do. But even the naturally unflexible have hope in this pose.
Warming up the body and the key muscles is important as is the consistency of practicing. The way to get better at hanumanasana is to do hanumanasana. Sounds simple, right? But then why do so many of us just avoid the pose altogether? Check out the following video for full split prep poses...
http://youtu.be/BgPTT6tQz20
Take inspiration from Hanuman, the monkey god for whom the pose is named before you take this leap of faith. Hanuman leaped across an ocean in order to help a friend he loved. And so this massive leap represents the expansion of his heart, the love that allowed him to take this step. In the full version of the pose we add in the expression of the heart opening. Take a look...and give hanumanasana another chance.
http://youtu.be/zUkMuJdOyZ4