Fast from all food, and to the extent safe, fluids during daylight hours.
Today marks the first full day of Ramadan. One way that Christians can journey with Muslims in this period of seeking submission to God is to follow the daily fast which extends from sunrise to sunset each day.
Other key practices of Ramadan that would be helpful for Christians are the offering of charity and reading through the Koran, a particularly helpful practice for Christians unfamiliar with Islam.
Since the time of St. Francis, Christians have been joining with Muslims in worship, not to say that our religions are the same, but to acknowledge that we are both seeking to submit our lives to God. Use this time of Ramadan to submit yourself to God and seek to meet and share conversations with Muslims who are pursuing the same. Explore with them what is different and what is common between our religions.