A modern day Wiccan coven is typically a small group of members led by a Wiccan Priestess. The coven celebrates the Turning of the Wheel which are the 8 holy days of the year. These seasonal holidays are called Sabbats.
Members of the coven might also meet monthly or more to pray, study, create magick and share concerns. These meetings are timed to the full moon and dark moon esbats. Believers in magick believe that you must know what you want to make your magick successful. Wiccans believe that magic with a specific focus will be more successful than general magick to fill random needs. For example a magick spell to make you life better is too nebulous where as a magick spell to make a certain aspect of your life such as relationships or beauty etc is more specific.
The focus needed to succeed is why witches enjoy spending so much time creating beautiful altars and gathering together all of the ingredients needed for a spell. This ritual of creating an environment for your spells hones your focus and has a soothing ritualistic effect much in the same way as practicing other faiths. Preparing for magick by gathering essential oils, stones, crystals, candles, incense, herbs and other materials will put you in the right state of mind for magick. Wiccans feel that a beautiful ritual can teach them life lessons and such learnings are in tune with and come at different times of life.