If you don't have a streching buddy at hand, try hanging on something - Hold onto a rail or something (preferably not too high off the ground, you don't want to hurt yourself if you fall) and just dangle for as long as you can. Or try lying on your back and pulling your legs up towards your chest one at a time. Make sure you keep the leg that is not being pulled up as flat as possible. Or try holding both your legs to your chest and rock your body head to bum. - My mom does this one all the time. Or if you do yoga, or are just really nimble, you can try lying on your back and picking up your legs and placing them over your head and try to touch the ground above your head with your toes. Finnally you can try sitting with the sole of your feet pressed against each other and bending over and trying to touch your nose to your feet.
sit with your legs straight out in front of you knees slightly bent and reach down and grab your toes, pull on your toes with your hands and push on your hands with your toes until you feel a stretching. your knees should be bent until you only feel the stretch in your lower back
Lie down on your back, hold onto something fixed in place, and get a friend to pull your legs out straight as hard as they can without hurting you. My mum and I do this all the time and it's a great way of stretching your back and legs without clicking it or anything.
seal stretch. you lay on your stomach and push up to a seal postion with your arms fully straigtened and hands on the floor.