Seaming a pillow

I am in the process of knitting a pillow and I am going to get to the point where I need to sew the corners together. Any suggestions on the best way to do this so that the pillow doesn’t fall apart? Any help will be appreciated. Thanks

Just the corners? If you mean the edges I’d probably use mattress stitch. There’s a video here under finishing techniques.

Some still photos here -

Yeah, I meant the edges. Your suggestions are really helpful. Thanks so much. I will give the mattress stitch a try.