Full name or nickname?!?

My legal first name is Kerrianne but everyone calls me Kerri...

So at what point do things need to have my fullname & what things can have a nickname?!?

For instance, I know the wedding invitation will have my full name but what else should need it!

I'm so confused! Can anyone help?

Do you prefer Kerri??

If you prefer Kerri I would say Kerri would work for most things( ex: Eparty invites, bridal shower invites), you just want to make sure your proper and use your legal name on your wedding invites and of course any contracts

crashing ....

my full name is Moran, but everyone calls me Mor .... i had 'Moran' on the invitations and that's pretty much it ... our favors say 'mor', i'll be annouced as 'mor' when i walk into the RH, etc.

I prefer Kerri....
his family only knows me as Kerri
and no one in my family calls me Kerri....

My name is Jennifer, everyone calls me Jen but I would never use Jen formally.
ETA: If I simply preferred Jen, the way you prefer Kerri, I probably would just use Kerri for everything. Except legal documents.