Here are some ideas for what you might want to include in an Altar to Ostara.
Ostara, the ancient German Virgin Goddess of Spring, loves bright colors. The light pastels of spring are perfect offerings for Ostara. To represent earth on your altar, choose bright or pastel colored stones like Rose Quartz, Amethyst, or any of the Calcites (blue, red, yellow, or green). If you have some Citrine, be sure to include it. Citrine has long been an aid for mental clarity.
By including an offering of colored eggs on your altar, you will be taking part in an ancient tradition (still performed!) by the Germanic people. Ostara has been honored this time of year with painted eggs for centuries.
To symbolize fertility, in addition to the eggs, you can include seeds or rice on your altar.
Incense and feathers are perfect symbols for air on your altar. It is important for Ostara's altar that you include a symbol for air because Ostara herself is the living symbol for Air. (This must be the way Ostara and Easter became associated with birds, i.e. chickens) Be sure to burn incense at your altar when you are dedicating it to bring in the energy and vibrational qualities of Ostara.
The perfect time to dedicate your altar is at dawn. Choose a day, then plan to dedicate your altar to Ostara at dawn's first light by lighting incense and repeating an invocation to her as well as a prayer of thanksgiving for all that Ostara symbolizes in your life:
A clear mind.
Fertility, either for the purpose of bearing a child or for creativity such as arts and crafts, writing, or decorating.
You can include anything you like on your altar to Ostara. You will know by how you feel if an item is appropriate or not. It is important to include symbols for the four elements on the altars. The four elements are Fire, Earth, Air, and Water. The four Calcites on the altar (red/fire, green/earth, yellow/air, and blue/water) represent Mother Earth and the four elements. Add feathers and other items that symbolize Ostara to the altar as offerings to her.