Saw this costume in person, and Penlowe pretty much has it right. The straps are just strips of the canvas/sackcloth braided together, and it's not a very fitted looking top. It's meant to look like it's made from horsehair/horsehide and straw or grass, as those would probably be the primary materials the Dothraki used. They ride horses, eat horses, and obviously would also wear horses.
Costume Con - Kili in a dress
Atomic Lollipop - Come visit me at the Make-Your-Own-Button free craft booth!
Polar Chill - check out my costume DIY panel and workshop
FanExpo - Iron Man Mark VII version 2, Pacific Rim Jaeger pilot?
FanExpo - fem!Iron Man Mark VII - The Iron Man Armor Project
Atomic Lollipop - Vanellope von Schweetz; raver!Sailor Mars