Cutting fabric is a crucial step in curtain making, as a mistake may result in unnecessary joins or the need to buy more fabric.

Lay out the fabric where you have enough space to measure the full drop comfortably. Make sure the fabric is cut evenly across the width by pulling a thread. Use this as a cutting line, if necessary.

Cut away the selvedges to prevent the hems and seams puckering.

It looks better to have a full fabric width in the centre of the curtain if one curtain is to cover the window. If necessary, cut one width in half and sew one half to either side of the centre drop. The full width should be at the leading edge if you are using two curtains.

If you need to use half-widths of fabric, fold the drop in half lengthwise with the selvedges together and press in a crease. Use this fold as a guide when cutting.

Positioning patterned fabric
When you are using patterned fabric, it is important to match the pattern. Patterns printed on fabric are repeated evenly throughout the roll, normally every 15, 32 or 64cm.

First decide how the pattern will fit on the curtain. On floor-length curtains, the hem is usually the focal point and so a complete pattern should be seen at the bottom. Don't forget to allow for the hem. However, if the hem will be hidden by furniture, the complete pattern should appear at the top of the curtain.

On a sill-length curtain, the focal point or complete pattern is usually at the hem of the curtain. If there is a dominant pattern running vertically, it should, as far as possible, run down the centre of the completed curtain.

Once you have decided on the pattern placement, cut the first drop accordingly, making sure to allow for the hem and heading. Then cut the other drops, allowing an extra pattern repeat on every other drop. This will give you the fabric to match the pattern across the full curtain.

Dealing with printed borders
Some fabrics have a border that runs vertically along one edge. This fabric can be cut in a number of ways to achieve different effects.

Two drops can be joined normally so there is a border along one edge and down the centre. The border can be cut off all drops except the leading edge (but remember this will alter the width of the fabric and you may need an extra drop). The leading edge will be at the centre of the window if you are using two curtains to cover the window, or on the outside if there will be only one.

The border can be cut from one width and sewn to the outer edge of the curtain so there is a border down both sides. An extra length of the border can also be sewn across the bottom of the curtain - always add the side borders before adding the bottom so that you can calculate the length of the bottom border.

Source: Making Your Own Curtains (Murdoch Books)