While searching for a simple crafting activity for my cousin for his school, came across this samurai helmet (origami). So after making one I found alternate usage as a bookmark. Its simple and takes just a minute or two.

Step 1: Materials

a square piece of paper
ruler - optional

for the paper you can take a plain white sheet or dual colored or an advertising pamphlet with bright colors would do quite good. i found only a plain sheet of paper so i shaded one side with a color pencil. for dimensions of the sheet its up to you , i took a 3 inch X 3 inch so the final origami is not too small or too big.

the ruler is to help you make fold straight.

Step 2: Base Fold

fold the paper diagonally. I am naming the angles as A,B,C for explanation purpose.

Step 3: Fold 2

fold the angles A,C down towards B and make sure to leave some gap as in the pic.

Step 4: Fold 3

now fold A,C upwards as in the pic.

Step 5: Fold 4

now again fold A,C downwards as shown.

Step 6: Folds 5 & 6

now fold the top layer at B upwards such that it forms a small inner triangle and a small band is formed .
fold the band upwards.

Step 7: Fold 7

now fold the remaining triangular layer up and in to the gap. there you have your samurai helmet.
mount it at the corner of a page to use it as a bookmark.