Goblet pleats can be made with heading tapes but when they are stitched by hand the superior end result is well worth the extra effort. This professional look is achieved with a minimal amount of stitching showing on the right side of the fabric and are suitable for lined curtains, valances and bed drapes. These headings require between 2 and 2½ times the pole length with the fabric pleated to the exact length of the pole with the fullness coming from the pleats. Trimmings, such as buttons and cord, can be stitched to the base of the goblets to enhance the look.
When planning these hand made headings there are some points to take into consideration.
These types of headings, when used on curtains, are best suited to hang using a decorative pole.
The length of the Goblet pleats must be in proportion, for example 3" - 4" (7.5 - 10 cms) for valances and 3" - 8" (7.5 - 20 cms) for curtains.
All curtains or valances in the same room must have the same fullness ratio i.e. the size of the pleats and spacings must be the same with the widths of fabric adjusted to accommodate this.
For valances with returns (the sides of the pelmet board or valance rail) position the pleats on the front edge leaving flat spaces for the returns.
These instructions are based on working out the size of the pleats and spaces before actually making the curtains. Whilst there are numerous other ways of making Goblet pleated curtains and valances I personally always use this method as I believe it is simpler to calculate.
These free illustrated instructions will enable you to make your own Goblet pleat headings for your window treatments.

Requirements:

Fabric of choice.

Lining fabric.

Matching thread.

Fabric marker or pencil.

Large Set Square.

Cover buttons/cord (optional)

Curtain buckram wide enough for the length of the pleats.

Calculating the pleats and spaces:

The size of the pleats and spaces can vary in order to arrive at the desired width of curtain. I find it is easier to calculate the pleats and spacings and adjust the flat curtain to the required width. This eliminates the possibility of working with awkward measurements e.g. pleat widths which worked out at 4.67234 inches. A good starting point is to have 6 - 8 pleats per yard or metre.
This is not a rigid rule however as your own personal choice may be for wide curtains with numerous smaller pleats closer together or narrow curtains with fewer but larger pleats.

Please note that when calculating for a Valance use the track width minus the returns (sides). Do not halve it before calculating for the pleats and spaces but add the returns measurement to the flat width after calculating the width of valance required. The returns measurements are then marked at each side. For valances which are to be attached to a pelmet or cornice board with pins or Velcro there is no need to add an allowance for springback.

Measure the length of the curtain pole between the inside edges of the finials and halve it.

To this measurement add 4" (10 cms) for springback. This is the amount the curtain relaxes when hung. This gives you the finished pleated width of each curtain .

Based on 6 - 8 pleats per yard/metre decide on how many pleats you require. This will also be the number of spaces as there will be a space between each pleat and a half space at each end. Let's call the number of pleats .

Divide length by to give you the width of each space. We will call this . At this point common sense must prevail because dividing numbers in this way can and will produce results, which in the real world, you could not work with. It is therefore necessary to round either up or down the value of . I personally always round to the nearest 8th of an inch.
This revised figure will now become .

An example might help:
Finished width = 50" : Number of pleats = 9 : 50 divided by 9 = 5.5555555 : This is not a figure that you can realistically work with (at least not on my tape measure !!) so use 5.5. What am I losing by this ? 9 multiplied by 5.5 = 49.5 which means you have lost ½" which is not a critical loss.

For a fullness ratio of 2 your pleats need to be the same size as your spaces (). For fuller curtains i.e. a higher fullness ratio increase the size of the pleats. Having decided on your pleat size call this figure .
By making the pleats the same size as the spaces ( fullness ratio of 2 ) the finished curtain is symmetrical. If the pleats are much smaller than the spaces the curtains can look out of proportion. If the pleats are too large they can be overpowering and you may not see the spaces. Again it is a matter of choice.

You now need to work out how much fabric is required for the pleats alone. To do this multiply the number of pleats by the width of each pleat . We will call this .

Finally we need to work out the width we need to make our flat curtain in order to achieve the right number of spaces and pleats in the sizes we have decided upon. To do this multiply the number of spaces by the width of each space and to this result add .

You now need to make your lined curtain or valance to the required length and the width as calculated above.

Use our instructions until you come to the point where you have to attach the heading tape.

Marking the pleats and spaces:

Cut a length of buckram the width of the curtain or valance and insert it between the face fabric and the lining below the seam allowance. Tack in place.

Turn in the seam allowance at the top edge on the fabic and lining. slipstitch lining to fabric along top fold. Press in place.

Place the curtain right side down on a flat surface and mark the pleats and spaces with pins.

Once you are satisfied that the pleats and spaces are evenly marked draw a line with a fabric pen or pencil down the length of the buckram and at right angles to the top edge at each pin marker.

For valances that are to be attached by Velcro. Cut lengths of Velcro the width of each space. Pin one piece across each space close to the top edge. Backstitch in place along all 4 sides being careful not to take the stitches through to the right side.

Making Goblet pleats:

Working from the wrong side bring the 2 sides of the pleat together and pin down the length of the pleat at right angles to the top edge.

Machine stitch down the full length of the pleat i.e. the width of the buckram. Remove the tacking stitches.

Place the curtain right side up on a flat surface.

Squash the base of each pleat just below the buckram to form 3 smaller pleats. Be careful not to squash the goblet.

Using strong matching thread sew through all thicknesses to form the base of the goblet. Stitch about halfway between the top folds and the line of machine stitches so that the stitches will not show from the front.

Round each pleat into a goblet shape and stuff with tissue paper, wadding or cotton wool. I recently used short lengths of plastic water piping which by luck was the exact diameter I required.

Insert a pinhook at the back of each pleat at the required height.

To enhance the look cord can be looped between the base of the pleats. I used loops of cord twice the width of the spaces and stitched them at the base of each pleat. At each edge the cord was looped to the wrong side and secured in the side seams. To finish off I stitched a covered button at the base of each pleat.