Warm-ups are different for all of us, and anyone who says there is one that will fit everyone is beyond stupid. For many people a warm-up is more mental than physical, and for others there is almost no need for a warm-up at all. Band directors (myself included) do generic warm-ups in an attempt to help the whole band, but we need to realize that what we are doing is truly generic. As I'm getting older I find that I need a little more warm-up time than I did a few years ago, but for themost part, I'm still a person who needs almost no warm-up. On the other hand, if the playing conditions are cold in temperature I'm cooked, stick a fork in me, it's just not going to happen that day!. So try and develop a little warm up for yourself. I carried a flugelhorn leadpipe when I was in college and I would buzz on it while walking from class to class. You get some strange looks, but you also get some buzz time in! It may be a small answer to your question. By the way, I still do that in my car while driving to a gig.