Step 1 : Folding, measuring and drawing

Fold the sheet of paper in two, widthwise, and mark the fold with your fingernail. Place the ruler along the fold, draw a point 3 cm from the top of the and another 3 cm from the bottom of the page.

Step 2 : Drawing two parallel lines

Starting at these points, use the set square to draw two parallel lines perpendicular to the fold of the page, 7cm in length.

Step 3 : Cutting and folding

Use your scissors to cut the two lines you have drawn: make sure you cut accurately! Fold back this large piece of paper in one direction, and then in the other and mark the fold with your fingernail.

Step 4 : Folding back the paper

Place this large panel of folded paper on the inside of the sheet: you have formed the largest step of the stairs. Fold back your A4 sheet.

Step 5 : Make 2 smaller panels

Draw two parallel lines 2 cm above and below the new fold, 3 cm in length. Use your scissors to cut the four layers of paper following the lines drawn. Fold these two panels back in one direction and then in the other, marking the fold well. Remember to fold them back inside the sheet before proceeding. You have formed two new steps for your stairs.

Step 6 : Réaliser 4 volets encore plus petits

Draw two parallel lines 2 cm above and below, 1.5 cm in length. Use your scissors to cut the lines drawn. Cutting will be difficult as there are 8 layers of paper. Fold back the four panels in one direction and then the other, marking the fold well.

Step 7 : Folding back these smaller panels

Push the four new small panels inside the sheet with your finger to form the new steps. Fold the sheet back and press firmly over the entire sheet to mark the folds well. Open the sheet again; you have made a pop-up that you can place horizontally to form a stairs or vertically to create an accordion.

Tip: in order to avoid tearing the paper during this process, handle it very gently.