Hi Tiffany. Well you've come to the right place.
I've helped my girlfriend finish hers but it wasn't on a budget 
However, a girl on these boards called Cressie (please look for her Zam on a budget thread) has done one.
So best bet is to first make yourself familiar with all of Zam's costume parts. From a pic or these threads, and then check out Cressie's thread to see how she did it
Here's Cressie's thread.
http://www.thedentedhelmet.com/showthread.php?t=19778
Then there's a thread by Zam I Am, sticky up top, not Yvonne but the thread, that will help you get all the part names etc.
Hope that helps
John