Problem of file size in photoshop

[somendra]

Hii friends,

Can anyone tell me how to reduce file size of my google ppc remarketing campaign banners? I have designed all my banners with photoshop. I have read google guidelines. These guidelines shows google takes files of size 50kb or smaller than this.

[Pullo]

Hi there,

What format are the files currently in?
Which formats does Google accept?