Formal:
* كيف حالك؟ (Kayfa haluk?) - This is the most formal way to ask how someone is doing, used for strangers or people you respect greatly.
* كيف حالكم؟ (Kayfa halukum?) - This is the plural form used for addressing more than one person.
Informal:
* كيف حالك؟ (Kayfa haluk?) - The same phrase can be used informally, depending on your relationship with the person.
* شو اخبارك؟ (Shu akhbārak?) - This is a more casual and friendly way to ask, roughly translating to "What's new with you?"
* إيش اخبارك؟ (Eish akhbārak?) - This is another informal variation of the previous phrase, common in some Arabic dialects.
For a woman:
* كيف حالك؟ (Kayfa haluk?) - The same phrase is used, but pronounced with a different ending.
For a group of people:
* كيف حالكم؟ (Kayfa halukum?) - The plural form is used.
The best choice will depend on your relationship with the person you are speaking to.
Bonus:
* بخير (Bikhāyr) - This means "I'm fine" and is the common response to "how are you?"