Epson EPL-6100 Reference Manual page 178

5. Press the marked position on the left side of the handle to fold
the handle. Dispose of the used developer cartridge properly.
6. Remove the new developer cartridge from its bag. While
holding the cartridge horizontally, gently shake it a few times
from side to side and then from front to back to distribute the
toner evenly.
76 Replacing Consumable Products