Hi Rachel:

1)Make your curve
2)Copy this curve
3)Scale it

repeat now these steps for third curve and so on...
all curves must have same number of points,here an example from Andrei

https://www.youtube.com/watch?v=-H-CtJhD98s&x-yt-ts=1421914688&x-yt-cl=84503534


Do you want to know the start point of a closed curve that will be the seam of your loft?
download from here MarkCurveStart plug-in

http://moi3d.com/forum/messages.php?webtag=MOI&msg=5288.20&highlight=yes

here a further use of it

https://vimeo.com/63076359

M