how do you attach a photo onto these threads?

[Jade+Marley]

im quite new to this and i can just about write a new thread.. but with great difficulty.. and when i go to attach a photo it asks for a URL .. what do i do? as what website is my pictures on???? can you please help?? thankyou xx

 

[Spot_the_Risk]

GO to the Photo Gallery, there's a stickied thread there.