Creating a Wiccan Altar
There is not necessarily a "right" way of setting up an altar in Wicca. Ask ten Wiccans what's on their altars, you'll get thirteen different answers. If you're not following a specific tradition, you have the luxury of figuring out for yourself what works for you. There is a general structure to follow, but there's much room for creativity and individuality.
The magickal tools represent the elements. Candle and wand for Fire, incense and dagger for Air, chalice for Water, and pentacle for Earth. In addition to the tools, some like to include things from nature that represent the elements. Some possibilities are: a red stone or lava rock for Fire; a feather or flowers for Air; a seashell or bowl of water for Water; a pinecone or herbs for Earth.
The incense and dagger are placed on the east side of the altar, candle and wand on the south side, chalice on the west side, pentacle on the north side. The left side is for tools sacred to the Goddess (chalice, bell, pentacle, cauldron) and the right is for tools sacred to the God (incense, dagger, candle, wand).
The altar cloth really can be made of whatever material you like and color or pattern you like. Plain colored cloths seem to work the best for most occasions. Black is a popular choice. You could use colors that correspond to your interests or specialties in the Craft, such as a green cloth if you're interested in herbal magick, or purple for religion and spirituality. Patterned cloths are nice for Sabbats.
The altar stands in the middle of the circle, and is set to face either north for the Goddess and the Earth, or east, the place of fresh beginnings, where the Sun and Moon rise.
This isn't meant to be an all-encompassing list of altar items used to represent the elements and deities. Rather this is to give you an idea of the structure and creativeness involved, and to spark up your imagination. If some of these ideas don't appeal to you, look for items by taking a walk in a natural environment, or even your own home. Chances are you will stumble across something that speaks to you, that "tells" you it is meant to be a part of your altar. You can also check out the Fire, Water, Air, and Earth correspondences on this site for more ideas on what can be used.
http://www.asiya.org/bos/wiccanaltar.html