The Feast of Sacrifice celebrates the sacrifice that other living things- plant and animal- make so that we may live. An effigy is made out of materials on hand and stuffed with good things to eat. It is then "sacrificed" and the food is taken from it and made part of a ritual feast. There are two versions of this ritual. In one version the "victim" is destroyed by fire, and in the other the "victim" is beaten and torn apart.
The Wicker Man Effigy was made famous by The Wicker Man Movies, there are two, the old and the new. (The new one is horrible. The old one is a cult classic.) At harvest season we perform a modernized version of this ritual. We don't perform animal or human sacrifice, of course, but the act of making the effigy is a sacrifice in itself. The energies it creates is something along the lines of a mandala, it is a sacred art. Offerings can then be placed within the effigy and, in the tradition of the ancients, the people should partake of some of these offerings, making it a communal feast.
If you want to be literal, you can create a sacrifice in a human shape out of basket weaving material which you can get at any craft shop. I have done this and it takes a very long time. Some of us aren't good at this as others and prefer to use different methods. Paper mache might work, or you can build him out of cardboard boxes. Remember, it's the thought that counts. Remember also that it does not have to be a human shape. A generic animal shape is also suitable. The sacrifice is that of all things that suffer and die for our nourishment and animals do.
Once it's built, we fill him full of offerings. If he is going to be burned, the offerings are foil-wrapped goodies- all locally grown and freshly harvested. If he is to be beaten and torn apart, the offerings are individually wrapped candies and other treats.
Once the sacrifice is prepared we either sit him on the fire pit or hang him from a tree (yes, he is a pinata). We gather in a circle around him and offer up prayers of thanks for our food and other harvests. Then we file past him one by one and whisper prayers in his ear that we hope he will pass on to the Gods. Then we either light him up or distribute sticks and beat the stuffing out of him.
We sing and dance as he burns or as we beat him, remembering that for us to live, other things must die. Even if we are vegetarians, we take into our bodies the lives of plants, and thus they are immortal within us and we are immortal as well, because when we die, bacteria and worms will eat us and return us to the Earth. When the fire dies down, we dig out the food our effigy had within him and we have a great feast. While we eat, we keep in mind that we are literally eating the physical representation of the spirit of Earth, the Grain God, or the Harvest Goddess, whichever you prefer. That through us, it Is immortal, and through It, we are able to sustain our material lives.
This ritual can be performed at the Corn Moon, or the Harvest Moon, or at a First Harvest (beginning of August) or Second Harvest (Autumn Equinox) festival.