skin help

(i know how to change my skin)

ok im working on a grass type theme skin and i happen to have a problem changing the image.
what is the file, name, PNG Image ,what ever it is to change image (the blue base color showed below)?

Nice skin so far, I like the colours you used.
Back on topic… firstly, open the PMU Folder > Client > Skin > [“Grass skin”] > Game Window. Once you’re here, you need to create a background with the name: gui.png and with the size of; 850 x 640 - pixel.
This will replace that “blue background”.

thank you
is there a file that you put it inside or do i just save it on Game Window

yay im making new skin >:U

new skin=new problem :cry:
ok im make a twewy skin and well this keeps happenig

well the picture need to look like this

edit: NVM i got it