an approximation of an upper made from a different, usually much cheaper material than the intended final shoe, such as paper, to test the appearance of a design, the fit of pieces, afforded allowances, planned upper fitting order, fitting over a last, or other properties
Mockups are frequently used in patterning for bespoke work or mass production planning, often before sample shoes.
Mockups may be complete, with each pattern piece cut, turned, fitted, and even closed, or partial, with pieces simplified or omitted and glue or tape used instead of sewing.