You need this:

• 1 sheet of paper (size DIN A4)
• 1 pencil or pen
• 1 Lineal

You have to do this:

1. Place the sheet of paper on the floor and place your foot in the very center. 
2. Now draw the outline of your foot with a pencil or ballpoint pen. Start at the very front, on the big toe. 
3. After you have drawn the outline, measure its length with the ruler. To ensure that the shoe fits comfortably, add 1.5 cm to the measured length. 
4. With the help of the following size table for women's shoes, you can now find out which shoe size suits you.