Prepare files before importing into LightBurn: clean vector paths (remove stray nodes, unify overlapping shapes), convert text to outlines, and simplify complex nodes to improve processing speed. For raster images, desaturate and adjust contrast/levels to maximize engraving detail; resize to the target DPI for the material and laser resolution to avoid unnecessary file bloat. When converting bitmaps to vectors, choose algorithms that preserve intended detail without producing excessive nodes.