Preserving numbers is recommended when you are following a safe CMYK workflow. Preserving numbers is not recommended for printing RGB documents.
In Windows, right-click the printer you are using, and select Properties. Then locate the color management settings for the printer driver. For most printer drivers, color management settings are labeled Color Management or ICM.
In Mac OS, select the printer you are using, and select the color management option from the pop‑up menu. For most printer drivers, this option is labeled ColorSync.
Every printer driver has different color management options. If it’s not clear how to set color management options, consult your printer documentation.