Start with the application
Describe where the glass will be used and how it will be supported. A shelf, a cabinet insert and a display-case panel may need different materials, thicknesses and edge details. Ask IDS to review the complete application.
Separate opening size from finished glass size
Label whether your dimensions describe an opening or the finished piece. Do not assume a deduction or fit allowance. Note the units and drawing revision, and have final dimensions and tolerances confirmed before production.
Record each piece clearly
Give every different piece an identifier. Include width, height or diameter, quantity and orientation. For curves, notches, holes or irregular shapes, prepare a dimensioned drawing rather than relying on a photo alone.
Pause before anything is made
Check your brief against the intended installation and confirm the final specification with IDS. A concept preview is not an engineering check or a fabrication drawing. For safety-critical applications, use a qualified professional.