1. Fix pole or track 5-15cm above window frame, with the ends extending 10cm beyond window sides.

2. Measure track width and drop to floor to gain width and length of finished curtains, then add appropriate heading and hem allowances. For a pencil-pleat heading you need two-and-a-half times the pole or track width. To width measurement, add 24cm for side hems and, if applicable, allow for 1.5cm seams for joining fabric widths. To length, add 8cm for heading and 16cm for hem. Take the measurements to a furnishing fabric store and ask the staff how much fabric you need to buy.

3. If you’re joining fabric, place half-widths at curtain’s outside edge. Put right sides and raw edges together and join, allowing a 1.5cm seam.

4. Machine-stitch 6cm double hems at sides. Cut 8cm-wide pencil-pleat heading tape to width of curtain, plus an additional 3cm at each end. Knot strings at leading edge; leave other end loose. At the fabric top, turn down an 8cm fold to wrong side; press in place. Position tape along top edge, 1cm below fold. Tuck under raw ends of the tape and knotted strings at leading edge. Pin, baste and stitch edges of tape through all layers. Stitch an 8cm double hem at bottom. Pull loose strings to gather evenly. Knot ends, insert curtain hooks and hang curtain.