To anchor your floss without needing to use a knot you can use a pin stitch. This is useful when stitching blackwork, or if you are cross stitching but have confetti stitches (single stitches of a colour).
Stitch up through 1.
Down through 2.
This is a standard stitch.
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Go back up through 1.
Using the tip of the needle nudge the floss out of the wat and stitch down through the middle of the cloth weave as shown in 4.
Once through the fabric use the tip of your needle to push back the floss you nudged out of the way if needed.
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