When writing in 1st person and 3rd person-limited it's important to remember that the narrative shouldn't include any information that the point of view character isn't aware of.
A lot of times it's easy to forget that certain wording may not be the best choice for your narrative.
For example, you may write something like:
"You're cute," she said, biting her lip. The compliment turned my face red, and I shuffled from foot to foot.
Since this is written in first person, how does the narrator know his face has turned red? He can't actually see his own face unless he is looking into a mirror.
In this case, it might be better to write: The compliment made me blush, and I shuffled from foot to foot.
Or, even better: My face flushed hot at the compliment, and I shuffled from foot to foot.
In the last example, the narrative expresses a feeling instead of a visual characteristic, which is appropriate since it's in first person.
By making sure that your narrative is consistent with your character's point of view, you can ensure that your writing makes sense and is immersive.