The slit pocket is a nice detail that's quick and easy to sew, and can be added to any pattern or garment. The illustrations show the Marte coat as an example.

1. Cut two identical squares measuring at least 20 x 20 cm (four pieces if you want two pockets).

2. Place one piece on top of the garment, right sides together, where you want the pocket. Draw a straight line 2 cm down from the top edge of the pocket. Stop 2 cm from the edge at each end too.

3. Sew a straight seam around the line. The seam should look like a long, narrow, lying-down "V". Start 0.5 cm from the line and sew in towards its end. At the end of the line, stop with the needle down, turn the work and sew back. Try to end up 0.5 cm below the line when you reach the edge where you started.

4. Cut along the line. Stop 1 mm from the seam at the end, so you don't cut the seam.

5. Turn the pocket piece through the opening.

6. Press the opening gently with an iron. Mind the heat and don't press too hard, to avoid the seam showing through.

7. Place the second square on top of the first. Make sure all edges and corners meet.

8. Sew around the edge with a straight stitch and 1 cm seam allowance on all sides, except the side with the slit.

9. Finish the edge with a zigzag stitch or overlocker.