Start with the printhead parked and the filament path clear. Trim the spool end to remove any swollen or sharply bent section, then guide it through the runout sensor and PTFE tube.
Follow the Load command on the K1C screen. Set the extruder lock as shown for your machine revision, feed the filament until it reaches the drive and let the printer heat before extrusion. Do not force cold material through the nozzle. Continue until the strand is smooth and has the new color.
For unloading, choose Retract or Unload and wait for the hotend to reach temperature. The printer will pull material back. Release and remove it only when the interface tells you to. If the end forms a large plug that will not pass through the tube, stop rather than pulling hard against the sensor or extruder.
Creality’s current K1C maintenance table gives a specific rule for changing material types: unload at the old material’s temperature, load the new spool, then purge at the higher extrusion temperature of the two materials until the old plastic is gone. Set the nozzle back to the new material’s normal temperature afterward.
Keep light tension while rewinding the old spool and secure its end. A loose end can cross under another winding and create a delayed feed failure.
Between changes, keep spools sealed the way the general filament storage guide describes — a swollen or unusually soft section at the spool end is often an early sign of moisture, covered in the rundown of what absorbed moisture actually looks like in a strand. Once a new material is loaded and purged, the guide to matching slicer temperature and cooling settings to the new spool is the logical next step.