How to render custom postbit template?

[yestyle]

Hello,

I create a new template, named postbit_two duplicated from postbit template in Vbulletin.
and in pm_showpm template I want to call this
{vb:raw postbit_two} instead for {vb:raw postbit} existed

I read this thread : https://vborg.vbsupport.ru/showthread.php?t=228078
but It's still not working

can you show me details in steps

what codes I need to add ?
and
where to add code ?

Please support ?

Thank you