Celtic knots are a type of complex knot pattern, originally invented by the ancient Celts. Designing Celtic knots by hand, without the use of computer software, can be a difficult and daunting task. Use graph paper to first create an outline in pencil, before completing the knot in ink. Celtic knot designs are used to decorate greeting cards and wrapping paper, but you can also use them as a plan for creating 3D Celtic knots out of rope.
Measure and mark a section of the graph paper that is four squares tall and six squares wide using the ruler and pencil.
Draw a diagonal line going from the middle of the left side of the top left square, to the middle of the top side of the top left square. Locate the middle of the square below the top left corner square, and draw a diagonal line to the middle of the square to the right of the top left square. Repeat this process until you have drawn two diagonal lines through each square. Repeat this process with diagonal lines going the opposite way across the grid. Each square should have four diagonal lines within it.
Draw curves, in tangent to the diagonal lines created in Step 2, in the squares on the edge of the rectangle. In the four corner squares, draw two curves, one vertically and one horizontally -- both in tangent to the original diagonal lines.
Locate and draw several "breaks" on the grid. A "break" is an area where the braid or knot will loop over or under itself. Try and visualise what the breaks will look like prior to marking them. This step requires trial and error; if the "break" does not work, simply erase the pencil line and start again. Mark breaks with a 1-inch straight line.
Draw pencil diagonal lines around the knot-work. When you reach a "break," draw in a curved line at a tangent to the diagonal lines (if it is not already curved like in the outside edges).
Erase all of the diagonal and curved lines that are not part of the lines you created in Step 5. Erase all of the "breaks."
Draw two parallel pencil lines above and below all of the lines you created in Step 5. Leave a 0.1-inch gap between the Step 5 line and each of the parallel lines.
Erase the pencil lines created in Step 5. Go over the parallel lines created in Step 7 with an ink pen. Leave the ink to dry before erasing all of the pencil lines.
Start with a small, simple Celtic knot design before progressing onto more complex design patterns.