What is the difference between saying "a bit an expert" and "a bit of an expert"? In what situations do you use "of" after "a bit"?

Native speaker’s answer
Rebecca
In this context, "a bit" is used to soften a statement or make it less strong. In such cases, it is always followed by "of." Thus, "a bit an expert" would automatically be grammatically incorrect. Ex: I'm a bit of a klutz. => Used to make the statement ("I'm a klutz") less forceful Ex: I'd like a bit of the cake too, please. => Used to make the request less strong