How does one perform the rituals of 'Umrah?

For Umrah, there are three pillars without which it is invalid: Ihram, circumambulating the Kaaba (Tawaf), and the ritual walk between Safa and Marwah (Sa'i).

As for the obligatory acts, they are: entering Ihram from the Miqat, abstaining from sewn garments for men, and shaving or shortening the hair. Whoever omits any of these must offer a sacrifice (dam).

As for the recommended acts, they are many. Among them, before Ihram: clipping nails, shaving pubic hair, performing ghusl (ritual bath), and perfuming oneself.

After Ihram: reciting the Talbiyah and raising one's voice with it for men, stipulating "O Allah, if a hindrance prevents me, then my place of release is where You have hindered me," and saying "Labbayk Allahumma Umrah (Here I am, O Allah, for Umrah)."

During Tawaf: kissing the Black Stone (unless it leads to crowding), performing idtiba (uncovering the right shoulder) and ramal (light jogging) for men, increasing in remembrance (dhikr) and supplication (dua), and performing two rak'ahs of prayer afterwards.

During Sa'i: ascending Safa and saying "We begin with what Allah began with," jogging between the two green markers, and increasing in remembrance.

The general description of Umrah is: entering Ihram from the Miqat (or its parallel, or from the (Al-Hill) for residents of Makkah), reciting the Talbiyah until seeing the Kaaba, performing Tawaf around the Kaaba (while in a state of ritual purity), performing two rak'ahs of prayer behind Maqam Ibrahim, performing Sa'i between Safa and Marwah, and then shaving or shortening the hair.