Celtic interlace is built on beautiful mathematical logic — a single continuous line that weaves over and under itself with no beginning and no end. Early Christians saw in this an image of eternity. You will learn the step-by-step grid method, which requires patience but produces something genuinely extraordinary that you constructed yourself.
Graph paper (¼" grid works well), HB pencil, vinyl eraser, Micron 05 pen, ruler. Final panel approximately 5×7" within a rectangular border.
Understand the grid method before drawing. Celtic knotwork is built on a grid of dots, with diagonal lines connecting them. Watching a video tutorial (such as Aon Celtic's grid method) helps, but the written method below works on its own if a video isn't available.
Build the dot grid. On graph paper, lightly mark a rectangle of dots — start small, 6 columns by 4 rows, spaced two grid squares apart. Then mark a second set of dots offset diagonally between the first set, halfway between each pair. You now have a grid of primary dots with secondary dots in between.
Draw the bounding box. Outline the outer edge of your knot panel as a rectangle just outside the outermost row of dots. The strands will turn and reflect off this border — they never cross it.
Connect with diagonal lines. Lightly draw short diagonal segments between adjacent dots, creating a pattern of woven Xs across the grid. Where lines meet the border, they bounce back at right angles instead of crossing it. This produces the basic interlace shape — it should already look knot-like.
Add the over/under breaks. Where two strands cross, erase a tiny gap in the strand that should pass underneath. Alternate the over/under at every single crossing — over, under, over, under — going around the whole knot. This single step is what creates the woven, three-dimensional illusion. If you get an over/under wrong, the strand will look broken instead of continuous.
Thicken the strands and ink your final lines. Once the pattern is correct in pencil, draw a parallel line alongside each strand to give it width (about 2-3mm thick), then ink the outlines with a Micron pen. Let dry 10 minutes before erasing all pencil guidelines.
For your final panel, scale up to a larger grid (8×5 or bigger) and frame the finished knotwork within a decorative rectangular border, the way it would appear in a manuscript margin.
This project is genuinely difficult the first time. Plan to do 2–3 practice knots on scratch paper before your final panel. That practice is the real lesson — the finished panel looks good only because of what you learned in the attempts before it.