First of all roll out your dough into thin, big circle. It doesn't have to be a perfect circle, don't worry.
After you reached needed thickness, sprinkle some flour on top and roll it around the long stick.
At the end, move the stick forward like this, leaving some space:
Then again leave some space and move the stick back:
You will continue to fold the dough forward and backward with the help of the stick until all dough is folded up. Then put the stick aside and cut up equal 4 inch strips.
Then starting from the piece in th middle, unfold the pieces one by one putting them on top of each other. Sprinkle some flour on top of each strip/
Now cut up again 4 inch squares.
You will have some left over pieces of half quares or triangles, don't use them for "manti", just knead them all together and leave for another use.
Now you can place the squares on your work place and put 1 tbsp of filling and some cubes of lamb's tail fat to each piece of square and pinch "Manti"s!