In order to a footwear design from 2 dimension drawings to 3 dimension sample requires planning, analyzing, sourcing along with a set of skills, such as pattern making and cutting; sewing; utilizing right tools; understanding different machines, etc.
Before a footwear is able to assemble correctly based on design, a design must be full diagnosed and completely separated into pieces in the right order.
Is the stitching lined correctly? Is lining required in this design? Does this design require a heel stiffer and toe re-enforcement piece? Is it a full lined or half lined shoe?
Making a right sample of a design is the extension of understanding the design in the first place.