Pattern piece cut upside down

Pattern pieces that hang crookedly or twist once sewn were likely cut without aligning the grainline to the fabric's lengthwise threads. Measure the grainline arrow from the selvedge at both ends before pinning down.

A finished garment coming out drastically too big or small, even with correct sizing chosen, usually means a home-printed PDF pattern was printed without disabling page scaling. Always print and measure the test square first.

A garment that doesn't fit despite following the pattern comes from choosing a size by ready-to-wear labels rather than the pattern's own body measurements. Measure yourself and compare directly to the finished measurement chart.

Multi-size patterns nested together make it easy to accidentally follow a neighboring size's line partway around a piece. Trace or highlight the chosen size clearly before cutting, checking closely at every curve.

Pattern pieces ending up slightly distorted despite careful layout often come from fabric sliding under the pattern weights or shears as you cut. Use a rotary cutter with a mat, or weight the pattern heavily.