Any size square. Make square base=fold in 1/2 diagonally both directions & white side to white. Fold in 1/2 both directions color to color. Pinch & squish into square as shown.
Sink the top=fold point down (note it's folded point of square). Unfold. Pinch to mountain fold the center square. Push in center of square & pinch 'n squish back to square base.
Fold top edge down as shown on the front and back. Open it back up being careful to not open those folds. Turn over. Push on the puffy square in the center so it is flat.
Cutting. Lift up the folded edge & open slightly. Cut along the fold where I marked it. Do this on all four folded edges. Turn over.
Fold top diamond down. Fold top right point down & them the left. Now do the same w/ bottom 2 points. Cut along center crease...do not cut thru that little square on the front.
Option 1: fold along each edge as shown. Turn over & stick the right point under that little square. You might want to glue it in thre. Repeat w/ left.
Option 2 (top row): cut the bottoms for a nice points. Option 3 (bottom row): instead of folding this part, cut it off (where I drew lines). I like this option best.
Starting at top left corner & going clockwise: Option 1 (only folded), Option 2 (folded & cut), Option 4 (not mentioned earlier, but you can squish it flat), & Option 3 (cut only).