What different and more natural ways I could say the same?
What is the correct way to say to my daughter take care of herself when she is about to/ doing something dangerous. She is 2 and half years old.
Is it correct to say?

When running too fast.
Stop running so fast or your are going to fall?
Go slowly,
slow down,
take it easy

What other situations can occur?

The above is correct?
What different and more natural ways I could say the same?
What other phrases are common

Question

What different and more natural ways I could say the same?
What is the correct way to say to my daughter take care of herself when she is about to/ doing something dangerous. She is 2 and half years old.
Is it correct to say?

When running too fast.
Stop running so fast or your are going to fall?
Go slowly,
slow down,
take it easy

What other situations can occur?

The above is correct?
What different and more natural ways I could say the same?
What other phrases are common

Answer

Honey, be careful (e.g. if she's trying to do something dangerous)
Sweetie, slow down (e.g. if she's running to fast) or 
Your daughter's name, don't run so fast / don't run too fast

Generally, all of the one's you mentioned are fine except "take it easy" isn't really used.  I hear the phrase "take it easy" more in the context of if someone is angry and you're trying to calm them down so you tell them "calm down, take it easy" or someone describing a situation where they're just having a relaxing day and looking to just "take it easy".

Hope that helps!

Answer

Those are all correct and common.