We need a ruler to draw a square. Remember, at a square all parties are equal. Halve a square.
Further you will need to plan hyphens, a dotted line a circle form. On crossings the form densely adjoins, and here in corners we should measure. It is possible also to draw straight lines from corners to each other, the line passes under 45 degrees. Plan a hyphen, from each corner one and too distance.
Now connect a dotted line in a single whole and the equal circle is ready. If to train much, will be able to draw a circle without square. And in general exactly to draw a circle you can take any round subject and lead round it.