First, diy sewing post, finally. Haha
My Steps:
1) Do the measurement with paper and cut them out
2) Place the paper on the cloth and cut accordingly
3) Sew the edges of each piece (3)
4) Put them together by sewing all the corners and DONE
 
BEFORE
 


AFTER

Well, in the video I mentioned that my steps are kinda wrong... and how should I avoid them :)
*DONT stitch the BIG Piece together first. You should patch the small pieces to the BIG Piece then finally seal the BIG Piece.