Cascade blinds are where each fold is a bit longer than the one in front, so you see all the folds "cascading" neatly, but they are a pain to work out and don't fold up as small. All your folds will be equal.
Mydecozo has a lot of useful stuff including a video.
I have made quite a few Roman blinds just self taught from books. It's not exactly hard but you need some space to work and lay it all out, measure and cut.
Recently I've found the Merrick and Day book here (library or buy) has brilliantly detailed instructions for hand and machine sewing, as well as measuring up and working out the pleats etc. You can get all the supplies (cord, rods etc) on ebay although the first ones I made with wooden batten and dowel from B&Q!
I'd definitely line and add a blackout layer if it's a bedroom.
Try googling Clarke and Clarke for some nice coastal fabrics.
According to google it's easy to make a roman blind . Is it really?
I'm a self taught sewer and have done done embroidery, cross stitch, made curtains etc in the past (all hand sewn, not sewing machine) but made it up as I went along not really knowing how to do it properly.
Am thinking of embarking on making a roman blind but online instructions vary alot and I don't know the terminology to understand what to do. Does anyone know of any good websites or blogs giving instructions for dummies for a simple roman blind (don't want the sort with the plasticky frame, want the sort with a string pull IYKWIM) or any advice as to whether to do it or not? Also, is lining required? AM thinking of doing one to go with a bue/white/green costal type of room, so any recommendations for suitable material also gratefully received