Sock designing in photoshop

Hi there!

I'm still new to photoshop and i had the idea to design my own custom socks for my soccer-squad. Now im required to deliver a good and clear design for the production company (i'm using a chinese production company so i want to make sure its obvious how the socks should look). I already have created a design for the sock as a seperate image. Now i want to make it so that i have an image of how the design looks on a sock. 

I have an image of a white cotton sock for designing. Now i want to put my design into the sock. 

Like this for instance:

+design=

Do any of you know good tutorials or ways to do this inside photoshop? 

Any feedback is apreciated!!