Hello everyone, I'm fairly new at this so please be patient!

I'm having trouble making the roofs for a LB&SCR E1 model I'm making. It has a very complex shape at the front and back, along with being on a flat surface. The sides seem to be less of a problem as they're just an arc shape.

I'm using AutoCAD 2015 for my models. Anyone familiar with this program, I would really appreciate the help!

Thanks Javier!

(P.s. I'm having a bit of trouble navigating this site, if theres a page dedicated to this problem I could also use a link, Thanks!)