I am also confused by this technique.. I did research it but will not be able to concentrate on trying it till Hubby leaves... Here are the links I found... I hope they help.. Some have pics of different steps...
http://webpages.charter.net/jaccola/Quilting_in_Sections.html
http://www.hgtv.com/hgtv/cr_quilting/article/0,1789,HGTV_3298_1507325,00.html