Read one or two horizontal lines inside the drying square and keep shade modifiers attached to the same instruction.
What the symbol means
A horizontal line inside a square means lay the item flat to dry. A second horizontal line adds “drip”: lay it flat while still dripping wet. A diagonal shade line means keep that same drying process out of direct sunlight.
What to do
Lay the item flat on a suitable drying surface and shape it according to any written label instructions.
If the square contains two horizontal lines, do not extract all the water first; the mark specifies drip-flat drying.
If a diagonal shade line is present, keep the flat-drying item out of direct sunlight.
Read the line direction and modifiers
Use the whole mark, not only its outside shape.
dry flat
One horizontal line: dry flat.
Drip dry flat
Two horizontal lines: drip flat.
dry flat in shade
Horizontal line plus a diagonal shade line: dry flat in shade.
line dry
Vertical line: line dry. The direction of the line changes the method.
Put it into practice
Support the whole item on a suitable flat surface. Gently arrange its shape and sleeves; allow airflow around it.
1
Prepare a supporting surface
For a wool sweater labelled dry flat, use a flat drying mesh or a clean, pale, lint-free towel. Support the body and sleeves instead of letting wet fabric hang over an edge.
2
Arrange the garment without stretching
Ease the sweater back into its shape and smooth folds gently. Keep any written reshaping directions with the label; do not pull the knit longer or wider.
3
Let it air dry in the right place
Keep wool away from radiators and direct sun. For any fabric, retain a shade modifier when shown. Two horizontal lines mean drip flat: do not add a spin or towel squeeze that removes the water the instruction says to leave in.
Match the rest of your label
Use this as a reading aid and follow the complete garment label, including any written instructions.
Symbol sets can include regional variants. Home Cues labels known US variants explicitly in the full reference.