I've always wondered how this works. If, say, you call your baby Edward with the intention of him being called Ted day to day, when do you use Edward and when do you use Ted. Does it ever get confusing? We are considering a couple of names which we would shorten day to day but would like the full name on the birth certificate.
I use DS' nn all the time. I'm not sure I've ever called him by his full name - maybe a handful of times. I only use the longer name for official things or introducing him, although I do follow it up by saying he's known as his nn. DH uses his longer name more though, as does MIL.
You also need to consider a different nickname for the park/supermarket etc so that someone will come onto mumsnet and start a thread with the title 'You will not believe the child's name I heard in the park today! '
DS has been known by his nn since the day he was born, although it wasn't the intention for him to only be known by it. It's just turned out that way. So much so, that his actual name doesn't feel like his. It's never used by anyone, other than, say, people calling it out from a register for the first time.
I am definitely glad that he has a full name on his birth certificate, because while his nickname suits him down to the ground now aged 3, I can easily see that he might want something less boyish when he's a man. At least he has options.
We just went with the nn on the birth certificate as DH said, while I was still pg, when would you use the whole name? To tell her off? I thought he was right, it seemed silly when the name we wanted was the short version, and we both felt it was a name that would work on a child or an adult.
I've always been Star at home (Startail reserved for when I was naughty) and normally at school.
I was quite happy to remind teachers and anyway the head, deputy head and the reception teacher (his DW)all lived on my estate and I played with their DDs.
My DD2 are full name or unrelated nn at home. DD1's name doesn't really shorten.
DD2 has a very specific shortening that has to be spelt right she uses at school. (Combined classes at primary meant sometimes there were two of them, they had everyone very well trained in not mixing them up)
We introduce dd as nickname. He birth announcement said xxxx (to be known as xx). One friend said she preferred the longer version and could she use that and I said no. (obv if dd decides to use that that is fine)
Both mine have full names that I love but often they do get shortened.
DH chose DD1s name because he loves the shortened version, she's ended up being called the short version 95% of the time now.
DD2s name is relatively uncommon but shortens to a really commonly used name, I prefer and always use her full name but again DH loves the shortening and everyone else seems to have followed his lead in using it.
I hated the full version of my name when younger and insisted on a shortening quite early on, however now I'm glad I have a more 'grown up' full name to use professionally and keep my shortening for friends/family.
Rhubarb my parents did that too. But children often seek out a different "at school" name from their "at home" name, so they have had to put up with our being known by inventive shortenings and nicknames anyway.
I have no shortened version of their names and it makes me cringe when people shorten them as they are not really the type of name that have a "real" nick name, but quite often use other pet names that only i use for them that have nothing to do with their names.