Preparing for 1000 calorie workout?

I am on the final couple of weeks of FB Fit and have a 1000 calorie workout scheduled tomorrow. I have done one before and managed to push myself through it and felt amazing afterwards so I'm hoping for the same tomorrow.

So my question(s) is: What do you eat beforehand? How long do you wait after you've eaten? What time of day do you do it?

I'm thinking of getting up early to avoid the heat as much as possible but want to make sure I'm properly fuelled. If anybody has any suggestions of what I could have then that would be great! Thanks :)