I've got my main cohorts of GCSEs this year, but I had to go back to school for 1 early AS result and 3 early GCSE results last year.
The week before the first set (the AS result), I was really nervous and not eating and stressing that I'd have got a B and that my Modern Foreign Languages department was right and that I shouldn't have taken AS French early and that it had all gone horribly wrong - so I asked a friend to come with me for support. It eventually transpired that I got a theoretical A*, but it helped to have that one friend there for support on the actual results day. We went Nando's and Boris-biking in Battersea Park afterwards, which are - of course - always, unequivocally delightful afternoon activities, be they taking place on results day or on any other day of the year
For the GCSE results, I was much less nervous given the success of the AS result. I met up again with friends and opened my results in front of my teachers. I was hoping to do it privately, but in hindsight, I was quite happy to be forced to open it in front of teachers: I'd got what I'd got and I'd have to face up to it publicly sooner or later, so it didn't matter who knew first or when exactly they did so. I let my friend open my AS result (so he knew my grade before I did) for similar reasons. It's not healthy, in my view, to place more importance on the results than they're due (given that your CV probably won't even declare them in one or two decades' time), so opening the results in front of friends or teachers is probably a better idea than wanting to hide and block the world out for the day.
So, based on my experience of last year, here's my advice (which I'll be taking when I open my own main-cohort GCSE results later this year):
1. Bring friends/ask friends to come if you think it would help.
2. Face up to the realisation that your grades are your grades - and don't be afraid to open them in front of whomever. What causes stress, anxiety and worry is when you place too much importance on something than said something is actually worth - and in the grand scheme of your life, your results won't matter too much. By wanting to open your results privately or mark the moment specially, you're only placing more importance on those results than they're due - so don't worry about where you open your results or how. Getting someone to open your results for you, or opening them in front of friends and/or teachers, might help this.
3. Please don't compare UMS scores. It's really annoying because it's (a) arrogant and (b) irrelevant, seeing as a difference of
x points might be down to inaccuracies or differences in marking anyway (which is coincidentally why few universities ask for A*A*A* at A-levels - they know that the exam boards can mark wrongly sometimes). It's actually very annoying and demeaning to compare UMS scores - at least a few of us left Results Day last year with furious expressions following some distasteful comments.
4. Go Nando's and some park somewhere with your friends afterwards and laugh it off