A flying geese unit is a rectangle, twice as wide as it is tall, with a large triangle — the goose — pointing across it and two smaller "sky" triangles filling the corners. Star blocks eat these units by the dozen, and if you make them one at a time by stitch-and-flipping squares onto a rectangle, you'll spend half your session cutting away perfectly good fabric and throwing it in the scrap bin. There's a better way, and it doesn't require buying a specialty ruler: one large square and four small squares, sewn and cut twice, yield four identical geese with no waste at all. I resisted this method for an embarrassingly long time because the cutting math looked fussy. It isn't — there are exactly two numbers to remember.
The cutting math, in two numbers
Decide the finished size of the goose you want — finished meaning the size it will be once it's sewn into the quilt, after all its seam allowances are eaten. A standard goose finishes twice as wide as tall: 2″ × 4″, 1½″ × 3″, 3″ × 6″. Then cut one large square at the finished width plus 1¼″, from your goose fabric, and four small squares at the finished height plus ⅞″, from your sky fabric. For a 2″ × 4″ finished goose, that's one 5¼″ square and four 2⅞″ squares. That's the whole formula. The odd-looking eighths exist because the diagonal seams need enough allowance to fold over cleanly — they aren't arbitrary, and rounding them off to the nearest quarter inch is how units come out too small.
First pass: two small squares and one drawn line
Place two of the small squares on the large square, right sides together, in opposite corners — their raw edges aligned with the large square's corners, their inner corners overlapping slightly at the center. Draw one diagonal line from corner to corner of the large square, running through both small squares. Sew a scant quarter inch away from the line on each side, then cut on the drawn line. You'll get two odd-looking units that quilters usually describe as hearts: a big triangle with two small triangles sticking up like ears. Press the small triangles open, away from the large fabric.
Second pass: one more square on each heart
Take one heart unit and lay the third small square right sides down on the remaining corner of the large fabric — the corner without ears. It will sit on point relative to the ears, edges lined up with the unit's raw edges. Draw a diagonal corner to corner on that square, sew a scant quarter inch on each side of the line, and cut on the line. Do the same with the fourth square on the other heart. Press the new small triangles open and you're holding four flying geese. The first time through takes maybe fifteen minutes with all the drawing and pressing; once the sequence is familiar, a batch of four takes about as long as a single stitch-and-flip goose used to take me, largely because chain piecing slots into this method beautifully — sew the first pass on a whole stack of large squares back to back, then the second pass the same way.
Why this beats one-at-a-time
The stitch-and-flip method — a rectangle plus two squares, sew across each square's diagonal, flip, trim away the layers underneath — is easier to visualize and fine for a block that needs two geese. But every goose it makes throws away four triangles of fabric, and the corners you trim off are exactly the size that's too small to be useful for anything else. Across the fifty-plus geese in a decent-sized star quilt, that's a visible pile of wasted yardage. The four-at-a-time method wastes nothing: every scrap of both squares ends up inside a unit. It's also more consistent in my experience, because all four geese in a batch inherit the same cutting and the same seams — if one is off, all four are off the same way, which is far easier to correct at the trimming stage than four independently wobbly units.
The honest tradeoff is that you can't preview a single unit before committing — the method produces four or none, in one fabric pairing. For a scrappy quilt where every goose is a different fabric combination, stitch-and-flip or even one of the specialty rulers may genuinely suit the project better. This method shines when a pattern wants stacks of identical geese.
Trimming, and where the point actually belongs
The unfinished size of a goose is its finished size plus half an inch each way — a 2″ × 4″ finished goose should measure 2½″ × 4″½ before it's sewn into anything. When you trim, the number that matters most isn't the outer dimension: it's the quarter inch of sky fabric above the goose's point. The point of the big triangle must sit exactly a quarter inch below the top raw edge, because that quarter inch is the seam allowance the next seam will consume. Line your ruler's quarter-inch mark on the point before you look at anything else, trim the top edge, then square the rest of the unit off that edge. Trim to the point first and the outer measurements almost take care of themselves; trim to the outer measurements first and the point ends up wherever it ends up.
When points still get chopped
Chopped points are the signature failure of flying geese, and with this method they almost always trace back to seam allowance drift on the two drawn-line passes rather than to the cutting. Sewing exactly a quarter inch from the drawn line — instead of scant — steals a thread or two of height from the goose on every pass, and it compounds: two passes of slightly-too-wide seams can move the finished point an eighth of an inch too low, which the next seam then slices through. The width of the drawn line itself matters too. A thick marker line can be a full sixteenth wide, and if you sew beside the line on its far side rather than kissing its near edge, you've silently widened your seam by that amount. Use a fine pencil, and sew so your needle just touches the line's edge on the side you're sewing.
Diagnose a batch before blaming your quarter inch, though. If the point sits low but the unit measures the right overall size, that's seam drift — press harder on scant. If the whole unit measures small and the point is proportionally fine, your squares were cut shy, and the oversize-and-trim approach from the note above is the reliable fix. And if one goose in the batch of four is off while its three siblings are fine, the culprit is nearly always pressing: an ear that didn't open fully against the seam leaves a fold of hidden fabric that shortens the unit. Re-press that seam from the front, run a fingernail or a seam roller along it, and the missing height usually reappears.