It should be clear that while performing obligatory ghusl, what is important is that water reaches the entire body including the rectum.
Sheikh Ahmad Kutty, a senior lecturer and Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states:
“The proper method of ghusl (ritual bath) involves the following steps:
1. Make the niyyah (intention) to perform ghusl for purification.
2. Wash your private parts thoroughly with water.
3. Perform wudu’ (ablution) except for washing of your feet, which you can do later while bathing the body.
4. Wash the entire body, starting with your head and the right side, followed by the left.
5. It is preferred that the whole body be washed three times. The minimum is once. Having completed the above, you are considered eligible to perform the salah (prayer).”