Good grief. I'm left handed. Always have been! 
Despite this, I have achieved grade 8, grade 5 and another grade 5 in instruments that I play 'right handedly'.
I sew left handedly having been taught by my right handed grandma.
I tried a LH fountain pen but it was more trouble than it was worth.
I can't use LH scissors because I've adapted the pressure I apply to make RH scissors work. I can't isolate what I do so I can't undo it to use LH ones. Cutting out is a bit tricky because the blade of the scissors obscures the line. But that's probably the biggest problem I have.
It never occurred to me/the teachers for me to sit on the left at school to avoid banging elbows. So I just kept my elbow tucked in and we got on with it!
I did put my book at an extreme angle but it never bothered anyone.
I held my pen in a standard RH way and yes I occasionally smudged my ink, but it was still legible (neat even) and I still passed my GCSEs, A Levels and got a first class degree and I'm also allowed to teach other people's children!!!
I do my ticks backwards and I make my class lists in reverse, with the names down the right so that I can tick them easily - which the children find amusing.
But that's it.
It's no big deal and parents who treat it as an issue irritate the hell out of me. It's not a flippin' disability. I just hold my pen in a different hand!
I do love it though when parents trot out the "yes, but he's left handed..." as an excuse/reason for everything. Sort of stops them dead when they realise I am too!