To make an exact-size reproduction of a flat pattern, first trace the pattern. Then position the tracing with a sheet of carbon paper over the new surface, and retrace the lines, using a hard pencil, a ballpoint pen, or (on wood and other rough surfaces) a dressmaker’s tracing wheel.
If you wish to enlarge a pattern, draw a grid of uniform squares over the original tracing; then draw a proportionally larger grid onto the new surface, dividing it into the same number of squares.
Copy the pattern by hand from the original onto the new surface, using the relationships of the squares to the pattern lines as a guide. For very precise work, add diagonal lines to all or part of each grid, further subdividing the squares.