how can i extend local area on usb build?

hi fellas.

i am using kali live 1.0.7 on my 16gb usb drive. both on bt5r3, i can't extend my local area.

http://i.imgur.com/LKYfpeA.png

**as seen on screenshot**
sda1= local > size 2.75gb (automatic?)
sda2= my storage area > size 11.69

i want to make sda1 size to 6gb, sda2 size to remaining 8,5 gb. making this is one of my life missions. :p