Is there any hard and fast rule on where the preposition should go in phrases like this, or is it open to personal preference?
Traditionally the object of the verb comes directly after the verb and that is usually the preferred word order.
With phrasal verbs the lines are blurred a bit, but consider it with a scenario that is not a phrasal verb:
I put the book on the table.
verb = put
object of verb= the book
preposition = on
If you ordered it like this, it would be odd:
I put on the table the book.
But with a phrasal verb like "put on" (as in your clothes) it is often used either way.
e.g. "Put on your clothes son" or "Put your clothes on son"