This is an incredibly debated subject.

There are a few undeniable God Modding actions, such as killing a character outright without consent of anyone.

However, a lot of people also consider anything relating to another character as God Modding, such as cutting them.

Example

Rose's eyes flashed with hate and she lashed out her katar, slicing Autumn's cheek before anyone could pull her away.

This is... not what I consider God Modding. Small, inconsequential cuts or even shoving don't fall into that category, especially because a lot of people who consider it God Modding would have dodged it, even if it would be impossible.

This is also a well-debated part of God Modding - dodging.

Some dodging is okay, especially when the characters are unequal and there is ample room.

Example

In the wide open field, Ezra slashed his knife at Kira, aiming to give a brutal blow to her stomach.

Kira jerked backwards, the demon faster than Ezra.

This is okay! (Notice how the "brutal blow" was aimed and didn't say landed. This is what you normally should do in this case.)

What is not okay?

Example

In the small, cramped cave, Nathaniel leapt at Victor and aimed for his heart. The blow missed and instead hit his arm.

But Victor jumped back in time, saving his arm.

Not okay, as Victor and Nathaniel are relatively evenly matched and the cave is cramped. Also, notice how the killing blow missed.

So, what I'm going to say is this:

When in an RP that has a lot of fighting, expect your characters to be injured and injure others, but never kill or seriously wound without consent.

When in an RP that does not have a lot of violence, first try to find away around it and then don't damage too much.