Islamic commandments :
Shahadah : Believe in One God, and One God only.
Salah : Prayers in 5 time slots, each day, which takes about 5 to 10 minutes every time.
Jakah : Giving out 2.5% of one's cash asset each year as charity.
Saom : Fasting for 30 days yearly in the month of Ramadan, from dawn to dusk everyday.
Hajj : Pilgrimage once in life. Visting Mecca when it's time.
These five are the fundamentals of the religion. And whoever fulfills those is a Muslim.