The first thing you do is draw a straight line. It can be any length. Then draw a point above the line.
Step 2: Steps Two & Three
Place the stylus of the compass on the point, and swing the compass down to make two marks on the line. These points of intersection are equidistant from the original point. Then, draw marks below the line, by placing the stylus on the points of intersection. Draw a line from where these two meet to the original point (the red arrow marks this)
Step 3: Step Four & Five
Mark two points on the 2nd line by placing the compass stylus on the original (red arrow) dot, and swinging it down and up. Then, swing the compass from both of these new pointsof intersection , on either side of the line, to form 2 new points.
Step 4: Step Five
Connect these 3 points, and now you have 2 parallel lines! The original line and the most recently made are parallel with each other. This is because you formed 2 perpendicular lines, which are 90 degrees each. The 90 degrees x2 equals 180 degrees, therefore producing parallel lines.