Easy- Get up in the morning and put food out for them. Either be available to refill it when it's empty, or use a big enough feeder/multiple feeders to last all day. Take the feed away in the evening. It doesn't have to be perfect. They don't need food at the crack of dawn, and if you forget to take food away occasionally, or they run out early, it's not a huge deal. I work afternoons, so I get up, get the kids ready, then around 10am, go feed the chickens. I take the food away when I get home from work around 11pm.
Looking4ewes- I'm not sure how light affects them in terms of weight gain. I pasture raise mine. I can say that the more natural light they get, the better. This year, I switched my brooder from being a cardboard box in my garage, into a standalone shed with several windows all around. My birds have done much better. Also, being locked up, they are probably getting exposed to dust and airborne fecal particles, which is hard on them. Pasture raising solves all of that, and keeps the poo smell/problem to a minimum also. Don't worry about cold at this point. After about a month of age, Cornish X's can easily handle freezing temps. While you won't hurt them by keeping a light on them, it's not necessary. They are much different from layers, and most of what you read in books regarding temperature and housing requirements doesn't apply. For example, I can comfortably put 75 Cornish X's in an unheated 10x10 tractor that they stay in 24/7 from three weeks until butchering, without a problem.