Formal:
* 今天过得怎么样？ (Jīntiān guò de zěnme yàng?) - This is a general and polite way to ask how someone's day is going.
* 您今天感觉怎么样？ (Nín jīntiān gǎnjué zěnme yàng?) - This is a more formal way to ask about someone's well-being.
Informal:
* 今天怎么样？ (Jīntiān zěnme yàng?) - This is a casual way to ask how someone's day is going.
* 今天过得还好吗？ (Jīntiān guò de hái hǎo ma?) - This is a slightly more polite way to ask if someone's day is going well.
* 最近怎么样？ (Zuìjìn zěnme yàng?) - This is a way to ask how someone has been doing in general.
Other options:
* 你今天怎么样？ (Nǐ jīntiān zěnme yàng?) - This is a more personal way to ask someone how they are doing.
* 最近还好吗？ (Zuìjìn hái hǎo ma?) - This is another way to ask how someone has been doing in general.
Tips:
* When speaking to someone older or in a position of authority, use the more formal phrases.
* When speaking to friends or family, you can use the more informal phrases.
* Be prepared to share your own day in response! It's common to reciprocate the question with a brief answer about how you're doing.
Remember that the best way to say "how are you doing today" in Chinese depends on the specific situation and who you are speaking to.