If you don't know how to replace ink HP printer cartridge, then you have come to the right place! Firstly, turn on your HP printer and lower the ink cartridge access door. Now, once the carriage moved to the center, press the ink cartridge to release it from its slot. Unpack the new ink cartridges and remove the plastic tapes. Hold the ink cartridge from the sides and insert the ink cartridges carefully. Once done, close the printer access door.