Making a Nightwing mask (and other superhero masks) isn’t difficult at all! You can easily craft one yourself even if you’re not an experienced cosplayer!

First of all you have to get hold of a small piece of Wonderflex or Worbla’s Finest Art. (Approx. 25cm x 10cm.)
Before you can cut out the basic form of your mask out of Wonderflex or WFA you have to prepare a stencil out of paper. Look for stencils on google, print them out and alter them accordingly to the mask you want to make.
Don’t forget to try on your paper stencil in front of a mirror! You should make sure the eye holes of your mask are big enough and in the right place, etc.
As soon as you’re satisfied with your stencil copy the shape of it onto your piece of Wonderflex/WFA and cut it out. File off the edges with sandpaper.

As soon as you’re done with these preparations you can move on to the “trickiest” part - Adjusting the mask to your face. (For this step it is really handy to have a friend or family member around who gives you a hand.)
Place the basic form of your mask on a heat-resitant surface and warm it up with a hairdryer until it is bendable. Place it on your face and press it into shape with your fingers carefully.
After 1-2 minutes the material should be solid again. You can now take it off your face.
If you’re content with the shape of your mask you’re finished. In case that there are a few parts of the mask you’re not happy with head the material up and adjust it again.

Afterwards you simply have to paint your mask with acrylic paint. To make sure the colour of the mask doesn’t rub off on your face spray it with transparent varnish. And that’s it!

As I already pointed out it’s really easy! I made my Stephanie Brown!Robin Mask this way! If you’re interested I could put up an illustrated tutorial for these masks. Just let me know!