Kami-dana is a household alter which is like a small shrine. Some companies or houses have Kami-dana at their places and pray to god.
Here are what to prepare for Kami-dana: 「棚板」Shelf board, which represents a sanctuary area, 「お宮」Shinto shrine, home for god, 「神具」Shingu (ritual articles) and 「しめ縄」Rope which is for protecting god’s world. Finally, 「御札」 Ofuda (charm) should be prepared to call in god. Ofuda can be purchased at a shrine
Kami-dana is recommended to place in a well-lighted and clean area and also on a high place close to a wall. Foods such as fruits, sweets etc. are offered before Kami-dana and rice, salt and water are changed every day and sake and sakaki (cleyera japonica) are changed every month.