Order of a PhD application in the United States
Does it look something like the following?

Please include information on

motivation
experience
Why this school?
...


If yes, I wouldn't worry about the order.
If, on the other hand, it is more like

Please include the following information in that order:

motivation
experience
Why this school?
...


then of course you should do that. However, I think it is rather uncommon to demand a fixed order, are you sure they want that?