Imposition scheme
4-page signature: Folio
A sheet printed with 2 pages per side and folded 1 time makes one 4-page signature — historically the Folio format.
Sheet layout
Folding sequence
Lay the sheet with side B facing up. Make a vertical fold (left over right). The last fold forms the spine on the left; the other folds are trimmed off at the head and fore-edge to free the pages.
Pages printed side by side across the spine fold always add up to 5 (for example 1 and 4) — a quick way to check any imposition.
Page positions
| Side | Top row | |
|---|---|---|
| A (outer) | 4 · 1 | |
| B (inner) | 2 · 3 |
↓ = printed upside down. Printers may use mirrored or rotated variants of this layout depending on press and folder.