Has to do with how one tells it (7)
I believe the answer is:
relates
'has to do with' is the definition.
('relate' can be a synonym of 'have to do with')
'one tells it' is the wordplay.
I cannot quite see how this works, but
'one' could be 'a' (a thing is one thing) and 'a' is found within the answer.
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is found within the answer.
This explanation may well be incorrect...
'how' is the link.
Can you help me to learn more?
(Other definitions for relates that I've seen before include "Narrates" , "Describes" , "couples" , "Tells (a tale)" .)