Overlay Crochet.

Here the raised stitches are made while the background grows. They are part of the row's structural count. They are not sewn on later, and they are not an extra line of slip stitches drawn across finished fabric.

Some overlay patterns use free top loops, some use post anchors, and some combine them. The stitch height, lower row, sideways offset and number of current positions replaced all belong in the definition. Do not substitute one insertion point because the finished texture looks similar.

A front-loop anchor carries the lower end of the stitch. It does not, by itself, tell you how many positions to leave unworked above. In this exercise each treble replaces exactly one current base. A cluster, increase or more elaborate design can have a different relationship.

Use smooth yarn, a suitable hook, two removable edge markers, another marker for the display face, scissors and a blunt yarn needle. Two compatible colours make the row pairs easier to distinguish. Call them A and B. Use supplies you already have; no fixed hook size, yarn quantity or finished measurement is required.

With A, chain thirteen. Single crochet in the second chain from the hook and every remaining chain: twelve stitches in row one. Mark the face towards you as the display face. It will face you again when working odd-numbered rows three and five.

Number the columns one to twelve in the order you worked row one. For right-handed crochet, column one is at the right edge of the display face; for left-handed crochet it is at the left. Those column names stay fixed when you turn. They are not a new count from whichever edge happens to be nearest.

Mark the first and last actual stitch tops at every working edge. Chain one before each later row and turn once. The chain never counts as a stitch in this sample.

After turning for row two, the reverse faces you. Work an ordinary single crochet through both top loops at each edge, with front-loop-only single crochet in the ten interior stitches. Count twelve tops.

Front and back describe the loops relative to the face you are working from. On this reverse-facing row, using the nearer front loop leaves the other strand exposed on the chosen display face. The row-one interior loops needed later remain free there.

Turn for row three. The display face is now towards you. Its ordinary interior single crochets will use the back loop only, leaving the nearer front strand available. At the two selected overlay positions, follow the lower-anchor instructions instead of making an ordinary background stitch.

Continue the same face rule: even rows use front loops for their interior background stitches; odd rows use back loops. Edge single crochets still use both loops. Do not change to BLO on every turned row: that would alternate the exposed strands between faces.

The raised stitch here is an ordinary US treble, called double treble in UK terminology, attached to an exposed loop two rows below. It begins with two yarn overs. It is not the US double crochet used in many overlay mosaic instructions.

1. Yarn over twice and find the specified free loop on the display face.
2. Insert beneath that one strand from below and out above it. Do not go through the background fabric or around a post.
3. Catch the yarn and draw up a loop to the current working height. Four loops are on the hook.
4. Yarn over and pull through two loops three times, leaving three, then two, then one active loop.

Keep the completed treble on the display face. Its length must reach its assigned top without dragging the lower loop upwards or leaving a hanging span. The diagonal also needs room to reach sideways. A named stitch height is a starting movement, not a guarantee that every yarn and tension will lie flat.

At the end of row two, change from A to B on the final pull-through of its last single crochet. Leave tails long enough to secure, then chain one and turn for row three. The chain is uncounted. Begin at fixed column one, with the display face towards you.

Use the following sequence:

• Column one: ordinary single crochet through both loops.
• Columns two and three: BLO single crochet.
• Column four: raised treble into the free display-side loop of row one, column five. Leave the top of row two, column four unworked.
• Columns five to eight: BLO single crochet into their row-two tops. The lower row-one anchor at column five does not prevent using the separate row-two top above it.
• Column nine: raised treble into the free display-side loop of row one, column eight. Leave the top of row two, column nine unworked.
• Columns ten and eleven: BLO single crochet.
• Column twelve: ordinary single crochet through both loops.

There are two edge single crochets, eight interior single crochets and two trebles: twelve new tops. The two lower anchor loops are not two additional positions in row three. No second background stitch is made at columns four or nine.

The diagonals lean in opposite directions on the display face. A left-handed version mirrors that physical appearance while keeping the same numbered relationships. Check the column labels against your starting edge before trying an asymmetric design.

Row four uses B. Chain one, turn and work ordinary single crochet at both edges, with front-loop-only single crochet in all ten interior tops, including the tops of the raised trebles. Count twelve. These tops are part of the row, not decorations to bypass.

Change back to A on the final pull-through of row four's last stitch. Chain one and turn for row five. The display face is towards you again, and fixed column one is the starting column.

In row five, work ordinary edges at one and twelve. Make a raised treble at column five into the free display-side loop of row three, column six. Make another at column eight into the free display-side loop of row three, column seven. Leave the immediate row-four bases at columns five and eight unworked.

Every other interior position receives one BLO single crochet. In working order, those plain interior columns are two, three, four, six, seven, nine, ten and eleven. Again, two edges plus eight interior single crochets plus two trebles gives twelve tops.

Row six uses A. Chain one, turn and work twelve single crochets: both loops at the edges and front loop only at the ten interior tops. Fasten off with a tail for securing. The sample now has six structural rows and four raised treble stitches on the chosen display face.

The four lower-to-upper relationships in this exercise are:

• Row one, column five anchors row three, column four.
• Row one, column eight anchors row three, column nine.
• Row three, column six anchors row five, column five.
• Row three, column seven anchors row five, column eight.

All four anchors are two rows below their new tops and one column to the side. Each raised stitch occupies one current position. This is a position map, not a universal symbol key or a chart for every kind of overlay stitch.

Mark a row complete only after counting its twelve actual tops and checking where each raised leg enters. The stitch-counting guide helps separate top Vs from long strands crossing the surface. A correct total does not prove that a diagonal uses the correct lower anchor.

If a required loop is hidden, first check the face, row number and column. On this turned sample, an even-row BLO stitch can put the spare strand on the wrong face. A stitch worked through both loops can consume it. Undo the affected section rather than splitting the yarn to invent a new anchor.

If the fabric puckers, check whether the anchor is too low or too far sideways, or whether the drawn-up loop was pulled short. If the treble hangs loose, check its length before completing the next stitches. Blocking is not a reliable cure for a wrongly placed leg.

Thirteen tops can mean a treble was added without leaving its current base unworked. Eleven can mean a base was skipped but its replacement was omitted. A treble into the wrong column can leave twelve tops while changing the motif, so inspect placement as well as arithmetic.

Secure the starting, colour-change and final tails on the reverse without dragging the diagonals out of position. The finishing lesson covers weaving through the fabric. Compare both faces with the sample relaxed; the reverse will not show the same relief.

Follow the care lesson and the yarn labels before washing or shaping. Measurements will depend on your yarn, hook and tension. Before using the technique in a larger item, assess how those choices and the stitch length behave together.

For another pattern, write down its background loop rule, working face, lower anchors, stitch definitions and resulting top counts. A round worked continuously from the display face may use BLO throughout; that does not make the alternating rule for these turned rows wrong. Keep each pattern's construction together rather than combining familiar fragments from different methods.