Buddhism has many methods to assist the dying Buddhist. Here is one for non-Buddhists that Tulku Thondup suggests. He has an entire chapter in his Peaceful Death, Joyful Rebirth
on helping the dying.
Even if the dying or dead person is not a Buddhist or not even open to Buddhism, the following formulas will be beneficial, safe, and respectful. Helpers can use them all or tailor any part of them that will suit the need of the particular dying person. They are based on Buddhist principles but have universal qualities and appeal.
In the sky above, imagine that you are seeing the source of blessings in the form of beings of light. These beings of great beauty, unconditional love, boundless joy, amazing peace, profound power, and total openness are sending light rays of warmth and joy in all directions with love.
See that beams of blessing lights are radiating from the source of blessings. These blessing lights are filling the whole atmosphere with a feeling of great peace and joy that dispels all the darkness of confusion, sadness, and fear.
Hear the singing sound of celebratory words, sounds, or prayers filling the atmosphere like a symphony. Feel the boundless joy, amazing peace, and total openness created by the vibrations of sound.
Think and feel that the deceased person is seeing the beautiful blessing lights, hearing the soothing sounds, and feeling the boundless love, peace, and openness, the qualities of the blessing light.
Finally, feel that you and the deceased person are merged in an indivisible state, in the womb of the boundless light of total peace and joy. Rest and relax in it for as long as you can. Do this again and again.
Now and then, express strong aspirations by thinking or saying, “May [name of the deceased] be with the blessing lights and enjoy peace and joy in the bardo [transition] and in all his or her future lives.”
This is what he means by 'source of blessings':
Source of blessings: In this book, this term denotes any object of prayer, reverence, refuge, protection,
and blessing. It could consist of any higher, inner, or true blessing sources such as buddhas, bodhisattvas,
saints, sages, or adept masters. Any mental object will be a powerful source of blessings if it has positive
qualities and is appreciated by the mind as positive. The dying and dead as well as their helpers must rely
on sources of blessings as the object or support for their prayers, meditations, and/or rites. The ultimate
source of blessings is in ourselves, as we all possess buddha-nature. However, until we have realized our
own potential, we must rely on an external source of blessings to awaken our own blessed nature and qualities.
May all seek, find and follow the Path of Tathāgatas.