I started the mask on Sunday July 15, 2012 with the sole intention of wearing the mask to the premier of The Dark Knight Rises on Thursday. I'm an amateur and knew there was no way I could get the latex technique down (having never worked with it before) and molded in time to look presentable. Instead I used a Paint respirator found here,
The respirator proved to be incredibly easy to work with and came with straps already which worked very well in securing the mask tightly to anyone's face.
For the detail on the front I used many of the ideas alexthemoviegeek had. Especially pens and noisemakers. These were easy to cut and just looked great when painted. I didnt want to buy expensive legos though and had no tools to make latex covers of so instead i found some ribbed plastic straws (the ones that accordian) and they worked great.
I also made the flaps a bit differently. I used velcro in the back. First the right flap attaches to the left flap horizontally. Then you just attach the top flap and adjust so the mask is at the right height. Sorry I don't have more pictures showing this but everyone that puts the mask on loves how easy it is and, more importantlly, how breathable it is.
I used mesh on the inside of the flaps instead of cloth to give it some more air. Also the paint respirator natually works well for normal breathing so that was no problem either.
All in all this project took me 15 hours of building time with about 3-4 hours of shopping time. I probably could have built it much quicker had I used a dremel instead of poor exacto knives for all of the cutting!
Hope this inspires you to go make your own mask and bring gotham to its reckoning. become the bat breaker!