Adding pockets to a down jacket

With considerable difficulty and mess. Me, I would put the pockets elsewhere.

Cheers

Construct two flaps – fabric, insulation, fabric, finish all the edges. Then just sew to the jacket around the perimeter leaving a hole for your hands. Kind of a kludge maybe?

Well the nano puff is synthetic, not down so may not be too messy.

Still probably not worth it in my opinion. However if dead set you can butcher something up. Sew a long thin rectangle (reminiscent of an oversized button hole) in the vertical direction where your hands will enter the pocket. Use another jacket with pockets for reference. Cut out the center the rectangle and finish the raw edges with some edge binding and/or a zipper. Then just sew on a back panel on the inside to make the actual pocket.

It'll probably end up fairly messy still and I wouldn't recommend the project.

I recently added a small zippered pocket to a life vest using this tutorial:

http://jembellish.blogspot.nl/2011/07/how-to-add-zip-pocket-to-shorts-in-5.html

Shouldn't be messy and the finished look is clean. Thin zippers (YKK 3C) will hardly add any weight. I believe my 12cm zipper weighs less than 5 grams.