Evisceration means fish, poultry or game disemboweling, removing the intestines (viscera, bowels).
Pull the soft belly up and make a cut where you can work in. You can now see the intestines, and see what you're doing. Cut, without touching the bowels, the belly open to the anus. Cut and tear as much as possible throughout the membranes that connect guts to carcass and meat. Carefully cut the ass out and bring it (the intestines) outside the carcass so that meat and organs are not soiled. Possibly you first tie the intestine close with a string.
Make lose everything from back to front and remove the entrails.
 You should not throw too much, actually just about anything is useful.

Pignet (peritoneum) is a solid film with fat wires that holds the intestines together. It is widely used to wrap delicate meats, sausages, kidneys, pate, liver, brains, poultry etc. for cooking or roasting.

The sternum can be split by sawing, cutting or chopping. For small animals a pruner is very handy. But you can also remove entrails from above and below.