1) The Declaration of Faith (Shahada)
This consists of the belief in and declaration of the words: “There is no deity but God, and Muhammad is the messenger of God.”
Muslims perform five obligatory prayers each day. Islamic prayers are a direct link between the worshiper and God. Islam has no hierarchical authority or priesthood. A learned Muslim chosen by each congregation leads the prayers.
3) Zakat (Charity)
One of the most important principles of Islam is that all things belong to God and that wealth is held in trust by human beings. Zakat, or charitable giving, “purifies” wealth by setting aside a portion for those in need. This payment is usually two and a half percent of one’s capital.
Every year in the Islamic lunar month of Ramadan, Muslims fast from first light until sunset. The fast is another method of self-purification.
A pilgrimage to Mecca, or Hajj, is an obligation for those who are physically or financially able.
Taken from: http://www-scf.usc.edu/~uscmhsa/aboutislam.html