There is nothing much to punctuating a sentence really, beyond a little comma sense. Yeah, yeah, I know what you're thinking--what's a misplaced, or forgotten comma or two? Like I said, commas can save lives!
You don't believe it? Take a look.
Jessica claimed Frankenstein planned the murder.
Without a comma, the angry villagers charge up the hill, torches blazing. But add a pair of commas, and Jessica becomes the suspect.
Cora, claimed Frankenstein, planned the murder.
Here's another example (remember you are at the Zombie Nite Cafe):
Let's eat Grandpa!
Let's eat, Grandpa!
In the first sentence, the Zombies are planning to eat Grandpa; the second, inviting him to dine with them.
Don't take commas for granted. Commas can save lives, or at the very least, avoid a misunderstanding.