cardio when is the best time??

ok so i've been doing HIIT now and was wondering when I should do it or if it matters. I've read and been told that the morning is the best time because you use your fat stores up but to be honest that's the last thing i want to do when i wake up. Running to the point of throwing up. another question. say i eat dinner at 6 pm and let my stomach digest it for say 4 hours, would this be better?

You should work out when it is most convenient for you. The best workout program is the one you actually follow consistantly.