Here are two lines of dialog:
"I don't know what order to put this in," says Max. "I don't know what order to put this in," Max says.
When is it better to use one over the other? Is one preferred over the other in writing? Should you keep the same order throughout the entire piece? If you should swap the order are there rules about when it would be good to use one over the other?
Short answer: you can use whichever you want, and there's no need to be consistent.
Long answer: you could, in theory, choose between them every time based on which works better — maybe if you really, really want to save the reveal of who's speaking until the last word for maximum punch — but honestly, I wouldn't overthink it. They're semantically identical, and any effect on your rhythm or cadence will be negligible. Unless you're writing poetry, your reader will barely register whether you used one or the other.
There are other ways to attribute dialogue, of course, and playing around with these will give you much more control over your impact:
You can also use no attribution at all, if it's already clear who's speaking.
'Your hat's on fire,' Eleanor said.
'Pardon?' said Jack.
'Your hat. It's on fire.'
This is a good way to maintain pace. It also creates a lot of white space on the page, which readers like.
Finally, you can use blocking and description to make clear who's speaking.
'Your hat's on fire,' Eleanor said. Jack waved a hand.
'My hat collection? Sweetie, the entire case is made of fire-resistant glass. It's state-of-the-art, brand new, there's no way it could–'
'No, your hat.' Eleanor pointed. 'The one on your head.'
'Oh! I thought it was warm.'
All of these are correct and have their place, but this last one in particular is a great way to achieve economy of words. If you resist the urge to be lazy with your beats, you can do much in a short space, and your readers will never have a chance to get bored.
Good luck!
I don't believe that one is preferred over the other or that you have to be consistent. However, I do believe that they signal something slightly different, at least in certain locales.
In the England I grew up in, "says Max" signals that Max's interjection is unexpected or cheeky. It might be used where a child interjects something into an adult conversation, for instance.
Whether that subtlety is more widespread or still current, however, is more than I can say.
