This stitch can be used wonderfully on the edges of the fabric to make a threaded effect. It can also be used in successive rows, and later trimmed and cut to make a velvet filling or a bushy effect. This tutorial will only teach you the technique of doing this stitch. Ideally, this stitch sits better on an even weave fabric, but you can also do it over a normal fabric, as illustrated.

Work between two closely drawn parallel stitch lines.

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Fig 1: Go in through A, and come out from B, in the lower stitch line. Leave the thread open.
Now, go in through C, a point directly above A and in the above stitch line. Keep the open thread towards the left, as shown. 
Fig 2: Bring the needle out through A as shown. 
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Fig 3: Now, take the needle in through D and out through A, as in the Fig 1.
Do not pull the thread all the way out. Instead, leave the loop at a length that you desire. 
Fig 4: Keeping the loop long, take the needle in through E, and out through D. 
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Fig 5: Keep up with this processes for the entire row. Remember to keep the loops hanging and at a similar length. You can either leave it like it is, especially if doing edgings.  Fig 6: Else, you can cut the loops to give it a different effect. You can make rows of such stitch to fill a given area. Later, you can cut and trim the threads for a bushy feel. In such a case, remember to begin form the bottom row and work upwards. This will keep you from begin bothered by the threads of the previous row!