There are many ceremonies for ancestors in the various spiritual traditions so I do not see any need to add to rather a large world collection. However, this is a little something which is less formal.
If you live near an ancestral burial ground for your own family, this is where you will work. If you do not, find the local burial ground and look for the oldest untended graves. These are someone's ancestors, but their memory is uncared for. By caring for (adopting) a forgotten ancestor, you are taking a step towards the consciousness of responsibility. Maybe someone somewhere is doing the same for your ancestors.
When you have found what you are looking for, take them a gift of food or wine. Put it on their graves and tell them, in your mind, about yourself. Tell them about your world, what is good and what is bad. Tend their grave, plant flowers, leave poems written and folded up.
It is not that they are hanging around listening; they will probably be well on their cycle of birth and death. It is much deeper than the personal. It is the respect and acknowledgment of what has been before. It is respecting the struggles that the early peoples went through so that we may have life. It honors their memory—which is all part of the building blocks of community.
If you choose to honor and tend a ceremonial burial (a mound, chamber etc. that is still intact) then it is a different story. The consciousness of that person is still there, tied to the land or tribe.
They offered themselves in sacrifice to act as an interface between the tribe and the people, or they agreed to such a burial so that they could stay within the consciousness of the land in service. This is why it is so destructive for archeologists to remove ceremonial burials: they are stripping the land of its human interface.
With such a burial, it is often easy to interact with the being that is there. Honor them and be quietly respectful. Offer your best wine and food as an energetic gift.
Do not try to perform ceremonies or magic in connection with them; that is just bad manners. Instead be a servant, a tender, to acknowledge them without interfering with their work.
I made contact with a woman in a ceremonial burial in Madison WI, where there are many such burial mounds. All she wanted was to be remembered. I offered her a ring of gold in friendship. It was a gold ear loop. Sometimes I wear the other one and leave one ear bare in her memory. So whenever I touch the naked lobe, I think of her and she is honored in her work. It is very simple and clear. That is all they want.
