I would have to say the easiest of Susan's would have to be the green one in the first. I have one almost like it and the blue top with the leather vest and purple flowing long skirt in PC. I found something like it at a theatre company and one of my friends made it just like Susan's. For Lucy, her blue one in LWW. It looks very easy to make. Just find the right fabric and you got it.

thank you so much, DamselJillPole! I thought that one looked the easiest, but I wanted some advice from more experienced sewing people.

I'm not all that great with sewing. I usually go to my best friend whom is brilliant at it and started when she was like a baby. haha

Good luck making your dress! and post pictures too

I do a lot of sewing dresses and it's not as easy as you think. I'd begin with a simple summer dress if you are new to sewing dresses - perhaps inspired by a Narnian dress? - before moving onto a more grander and intricate design.