Is it
this one? Because the instructions have explanatory pictures...
Regardless, if you're still lost, here's what you do(Not translated, but guessed):
-Cut out the parts for the hands completely, including the black parts.
-Bend the black parts 90 degrees so that, on the colored side, there is a corner and the whole thing takes on a sort of L shape. Do this for all four hands.
-Pair up the hands. How they work is that you take two that match and glue them together. They are glued on the un-colored parts and connected back to back on the purple parts, as shown in the instruction pictures in the link above. Each of the hands is by a number 2 or 3 on the sheet - match one of the 2s with one of the 3s to make a complete hand.
-Once you've done this you should have two pieces that, from the side, would amount to a T, with the flat part at the top being very short as it is made up of the black parts that we bent earlier. Then we take each hand, and glue them to the black areas on the side of Balrog, with the curved parts facing up. The black parts should reasonably match up.
-For the legs, fold those two white parts on either side twice - first fold once 90 degrees where they meet the colored foot part so they are sticking UP, away from the foot.
-Then, fold again at the line in the middle of them so they turn back in, forming a kind of overhang tab thing.
-Then, simply add glue to the top of both of these little tabs and stick them to the bottom of Balrog wherever you want his feet positioned, most likely facing forward. Be careful not to place them too awkwardly, as this is what Balrog is going to be standing on.
I can provide more helpful diagrams if that doesn't help.