Doing cardio on a empty stomach is muscle suicide. You need to suppress cortisol from the night fast as soon as you wake up. Have some oats before any training.
Obviously, if you're cutting, reduce the amount of oats.
On an empty stomach, your body will use the most readily available energy - muscle glycogen. Then, you'd burn muscles stupidily. Like I said, have some oats, and then do some long duration cardio-medium intensity (65% max HR) for maximum fat burning. (Or HIIT, which is a proven and very method too)
Doing cardio before weightlifting is not optimal. It will deplete your glycogen stores and your lifting will suffer. Doing cardio right after your weightlifting is out of question. At the time, you must be consuming your PWO shake, and nothing else.
You have to separate cardio from lifting by 6 to 8 hours.
For people who REALLY doesn't have the time to separate them, I'd suggest to do cardio first. You have to keep in mind that it's not optimal and as I said, you'll be already tired. Why not after ? PWO Shake. The most important meal with morning's one. You HAVE to consume it and not do anything else as soon as you've finished working out. Doing cardio at that time will be stupid, that will be killing your gains.
Hope that helps.