Are there any rules for writing accents in script format?

I plan on making a story that involves shape shifting so the MC needs to pay close attention to accents and little ticks that people do on their own. Think Lie to Me.

Do I just write:

PERSON
(Australian accent)
Hello there.

or

PERSON
'Ello thar.


note: if that is not Australian....sorry. Any good sites that have the rules of how various accents work?

 

1.accents are generally best indicated only with syntax, not oddball spellings...
2. that's not even close to an australian accent, sorry to say... 'thar' brings pirates to mind, not aussies...

my best advice is to study how the best writers of fiction [not necessarily the most popular ones] handle accents...

 

This.

It should be more about word choices than phonetics.