Mark the three points of your link on the surface. Start your thread where it will be covered by the beads. Bring your needle up at one of the side points and pick up enough beads to reach the next point while covering the centre point.
Take the needle down at the next point, then up at the third.
Draw the needle through and thread on the beads to match the other side. Pass the needle through the central bead and along the beads to point number two and down into the fabric.
Draw the thread through to tighten the link to finish.
Structure of stitch
Links are very useful and have many adaptions. They can be worked in a variety of bead combinations; over other stitches, sequins and beads for texture or worked corner to corner for a diamond trellis appearance.
The most important bead is the linking bead and making this a different colour or size, so it is easily recognisable as the stitches are worked, will help.
These three-pointed shapes can be evenly spaced or have two legs closer together. The legs can be all the same length with the same bead combination or all be different.
Various Authors, The Royal School of Needlework Book of Embroidery (2018) , p.380