I'm 5'8" and 150lbs. I've been doing lower body workouts with weights for the past month and a half and doing like 30mins on a treadmill 4times a week the rest. I want to get my arms going now to..(i was using weights before for my arms but stopped) My legs are getting defined but there is still fat so should i up my cardio??

Someone told me i should do 5mins of a warmup then do weights and then finish it off with my cardio...but if i'm trying to burn fat to should i do the cardio right when i wake up and then later on in the day do weights?
Any suggestions would be good.

Also i carry alot of fat in my flanks (i think thats what its called i seen it on tv called this) what are some good exercises to shrink this?? its noticeable and bugs the hell out of me! i'm currently trying to clean up my diet to so i know about that lol.

Give me some tips thanks!