I recently finished up a pair of AOU cap gauntlets. I started by using reference pictures from the movie and a Hot Toys figure to make a template in Gimp, and then printed it out onto poster paper. I simplified the design a bit to better suit a foam build.
I traced the shapes from the template onto 5mm and 3mm craft foam (I get my foam from Hobby Lobby), and cut them out with scissors. For the long and narrow lines at the base of the gauntlets, I used an xacto knife and a ruler instead of scissors to get straight and even cuts. All the pieces were then glued together using super glue (I like a brand called Rhino Glue). To keep consistent spacing, I placed scrap pieces of 2 and 3mm foam, turned on their side, in between the pieces while gluing them together. I found some thin cardboard laying around that was the perfect thickness for a spacer for the narrow lines as well.
Whenever you are gluing together several layers of foam that you want to stay in a curved position, it is best to hold them in that curved position while you glue them together. Otherwise the resulting flat block of foam will be too rigid to curve around your body. Alternatively, if there are only 2 or 3 layers of thin foam, you can glue everything flat on the table and then add an additional layer of either foam or nylon webbing to the inside of the item, and glue that layer on a curve. I made a simple cone-shaped tool to help with this, out of a large rolled up sheet of poster board paper stuffed with plastic grocery bags and taped shut. I bent the gauntlets around the cone and glued a length of nylon webbing along the inside of the top and bottom of the gauntlets, holding the foam in that curved position while the glue dried. I glued some velcro to the inside edges for fastening the gauntlets closed. The webbing on the hand piece is from strapworks.com.
To paint the gauntlets, I brushed on one thick coat of Benjamin Moore Aura to smooth out the texture of the foam a bit, and then 3 to 4 coats of regular acrylic paint from the craft store (brush-on as well). After painting I sprayed on a couple coats of clear plasti dip.
The template for the gauntlets is available here.