For both, decals and sweat from your example, you can do the following:
1) create a new material (gold/paint/etc);
2) enter Dynamask by clicking on the mask area;
3) select the black template;
4) click on "paint custom layer" (brush icon);
5) proceed working on the new layer the way you usually work in photoshop, pasting any mask images, painting with regular brushes, adding new layers if needed, etc;
6) click "Done".
Hi! Just as anubis suggest your best bet is to do a custom mask, you can either paint it manually which I would think is your best bet on the sweat, on the gold pattern I would suggest making a custom pattern, the tutorial for making custom patterns can be found here!
When you open Dynamask editor you have the option to either paint or use a bitmap (Grungemap) to custom mask out the part of the texture you want. It´s the three buttons at the bottom of Dynamask editor, A brush, an eraser, and a bitmap icon!
Replies
1) create a new material (gold/paint/etc);
2) enter Dynamask by clicking on the mask area;
3) select the black template;
4) click on "paint custom layer" (brush icon);
5) proceed working on the new layer the way you usually work in photoshop, pasting any mask images, painting with regular brushes, adding new layers if needed, etc;
6) click "Done".
Hope this helps a bit.