Clauses: comma splices and run-on sentences

Question

in case any of y'all were wondering, yes I did change my username, and no I don't have my Christmas tree up.

I was wondering how to avoid the comma splices in my writing. I find that a lot of the time, I have this really nice sentence that flows really well with another one, but they're separate sentences and I just place a comma in between them. It happens more often than I'd like to admit, but I'm humble.

The smell of something burning caught Haku’s attention, his eyes bugging out of his head and his mouth formed a perfect O shape, and he ninja rolled away to save his meal.

I thought this quote from my 10th chapter would get my point across. It starts with a cute sentence, "The smell of something burning caught Haku's attention."

And then it has an improper use of bug. It's meant to be "The smell of something burning caught Haku's attention. His eyes bugged out of his head and his mouth formed into a perfect O. He ninja rolled away from the conversation to save his meal."

That's better. But I have these types of sentences all over my novel. Help.

Answer 1

Usually, the Semi-Colon will be your best friend in these situations. They are designed to take two sentences that can flow together, but not quite. In the link provided, they show several examples of correct usage.

I ordered a cheeseburger for lunch; life’s too short for counting calories.

Money is the root of all evil; I don’t believe the reverse is necessarily true.

Martha has gone to the library; Andrew has gone to play soccer.

Answer 2

I have these types of sentences all over my novel. Help.

Our early drafts are usually full of bad writing habits. We fix these in editing and revision. So sharpen your red pencil and read through your work. Be ruthless.

Break your run-ons into shorter sentences, delete unnecessary stuff ("The smell of something burning caught Haku’s attention and he ninja rolled away to save his meal."), reword and reorganize your sentences, etc.