speaker cable tie-downs in room?

I know this is a dumb question .... I am installing some wall mounted speakers in my bedroom and would like to run the speaker cables in a manner which is unobtrusive. The walls are white I picked up some white, flat speaker cable and will run it along the floor and alongside a doorway, and finally across the wall to the speakers. My question is ... what do you use to pin down the cables?
I am looking for something not unsightly.

What do folks recommend?
I've tried my local home improvement stores with no luck.

Thx,
Rob