Not exactly qualified, since I haven't actually gained a "full sweep" (yet (hopefully)), but I have got As and A*s in everything I have done so far
Congrats on your A*s! What are the other 2 GCSEs you've completed besides maths? And what are the other 8 subjects to go?
Some general tips are:
Stay organised and make a realistic timetable (don't start as soon as you get home, keep room for sport/tv/food etc), make sure you stick to it, don't just do whatever you feel like and do it in 30 minute chunks, including a 5 minute break (STAY ACTIVE WITHIN THAT BREAK, walk around your house, get a drink, talk to someone about what you've learned).
Make notes with lots of colour and snazzy writing (don't worry if it's not perfect, you're the only one who'll ever see it - I should listen to that myself lol), rewrite them and condense them each time. Write things down multiple times without looking at where you're copying it from and it's bound to stick in your head).
Know your specification, mark schemes and typical exam questions - GCSEs don't branch out far from the specification and the same sorts of things come up again and again, chances are that if you've done enough questions there will be some repeats in the exam.
See friends regularly and don't talk about exams with them, make the most of your free time and don't become a revision monster.
TRY TEACHING THE CONCEPT YOU'RE REVISING TO SOMEONE ELSE - IT WORKS WONDERS. It really helps you understand the depth of what you're saying and it does stick in your mind.
Get the Exam Countdown app and plug in the dates of all of your exams/controlled assessment deadlines so that you can prioritise different subjects over others.
Make the most of the knowledge you have! You're likely to never be so knowledgable about so many different subject areas ever again, so enjoy being smart!
GO OUT THERE AND ACE THOSE EXAMS!!!!!!