For muscle: simple, easily digestible carbs (instant energy) then lifting weights. then simple carbs again after to reduce muscle wasting & help keep the muscle you just worked for. If possible working out in the afternoons rather than mornings (which are better for weight loss)
For fat: Eating a little extra at night is more comfortable coz you don't have to carry it around with you all day. Milk is excellent (its the natural fattening agent :) Nut milk or soy is way healthier, but chocolate milk/iced coffee does it all the same. Healthy oils are also beneficial to take by the tbs/tsp (eg. flaxseed oil, extra virgin olive oil) coz at least this way you know you are getting exclusively the good fats, without all the cr** that usually comes with fats & oils. It's ok not to be scared of fats and oils, the right ones are good for your heart and stomach, which will be important for your task. I like mashed avocado rolled in smoked salmon or ham.
Keeping digestion 'regular' will also help you feel less bloated and heavy, so fibre (cereals & veges) are good. And cordial/juices are a yum way to keep your fluids up for regularity!