im not trying to be a know all but here's a few tips that might come in handy..

when excersising make sure you do it before you eat your main meal of the day,this keeps your metabolism more consistant and it will continue to stay stable and burn on and off throughout the evening. a lot of people think you should excersise after eating thats not true! soon after eating the calores fat fibre and so on is absorbed so excersising with the intention of burning some of those cals is futile.
and rather than drinking water during your work out take an orange and have a segment or 2 from time to time.

during excersise especially cardio you retain too much fluid and salt when drinking water,(no thats nothing to do with salt in water lol, i mean the bodys natural salts such as potassium etc) which will actually slow down your heartrate a little and will make you feel slightly more sluggish, but the orange will refresh you and help keep your sugar levels and energy up.
hope thats of some help.