Allow your chicken to completely cool.
Decide what sized portions you will want. You can pull the chicken off the bone and shred it, or simply carve it so you have legs, wings etc with the bone still in.
If your portions are on the smaller side, wrap each portion in plastic wrap and/or aluminum foil. This way you can package several portions all in one container.
Pop your individually wrapped portions all into a freezer safe container or a freezer bag.
Secure the lid on your container. Or, zip your bag shut after you have squeezed any air out of it.
Use a marker to write the date on your package and then stick it in the freezer.