do you stretch and warm up. which first?

how long do you spend on it?

First it is important to warm up because it warms your muscles and keeps them loose. Then you go on to stretching, the stretches you do could depend on the martial art for example in Taekwondo it is key to be able to kick flexibly and high. To notice changes in your flexibility you should be stretching for up to 30 minutes at least 4 times a week.

You should first warm up with something like jumping jacks or running stairs, then stretch and hold each pose for 30 to 60 seconds. You should not overstretch because you could over do it and you should not understretch because you could pull a muscle. :P

Not a big fan of stretching. If I stretch I do it after the work out. If it was a hard work out. Other wise I don't bother.

its very important to stretch which I always do first then the warm up

It's funny how we wasted 45 minutes in Taekwondo just to stretch so your don't get your hamstrings to snap out. At first it hurts like hell, you'd get use to it eventually. Any legit TKD practitioner should know what I'm talking about.

do you stretch and warm up. which first?

how long do you spend on it?