Choose File > Print, adjust print settings, and click Save Preset. In the Save Preset dialog box that appears, either type a name in the text box or use the current name. (If the current name is an existing preset, saving overwrites that preset’s settings.) Click OK.

Choose Edit > Print Presets (Illustrator) or File > Print Presets > Define (InDesign), select a preset from the list, and then click Edit. Adjust print settings, and click OK to return to the Print Presets dialog box. Then click OK again.

You can edit the default preset as you would any other using the steps outlined above.