Junkers 101
Step 18
Add some more putty from the bottom of the visor to below the chin.  The layer mustn’t be too thick, though.  Form a rough mask shape with your sculpting tool/fingers ( a triangular mask always looks good on these guys), then smooth it out with your sculpting tool.  Now, ensure your sculpting tool is wet/lubircated, and, using the pointy end, gently press a couple of folds into the cloth mask you’ve just sculpted.  If you want a straight edge, you can wait for the putty to cure, then use a knife to cut a nice, straight edge.
The Finished Model!
Et voila! One dynamic Junker Legionary.  This pose would be ideal for the Desert Fox legion in particular, with their emphasis on speed.

Also, with only a small amount of work, you could convert this model into a thermite lancer, by replacing the sword with a spear-type weapon, or a suicide bomber, by leaving off all the weapons and the shield, and adding small rectangles of putty or plastic off-cuts to the torso area to represent the explosive charges.