I lost approx 4 stone, roughly 8 years ago - so not quite at the decade mark yet.
I did it through a combination of diet (specifically 5:2), healthy eating on eating days, cutting out nutritionally valueless foods (chocolate, cream cakes etc) reducing alcohol intake (it weakens my resolve - I think I look fabulous when I'm p*ed!) and gentle exercise - I walk every day for approx 45 mins.
Once I got down to a size I am happy with, I didn't move on to 6:1, as recommended by Michael Moseley, because I know my default position is to eat like a horse and drink like a fish.
I've continued with regular fast days and have maintained the weight loss.
I now do alternate days fasting, but, I now eat some things that I had cut out eg cheese.
I continue with low(ish) carbs as these are my weaknesses.
I have alcohol, generally, 1 day per week - couple of G and T's.
This also means that when I go on holiday or out with friends for meals, I eat and drink whatever I want, really enjoy it BUT then get back to the alternate fast days as soon as I get home.
I didn't weigh myself when trying to lose weight, as I knew that having deprived myself all week then finding I'd lost 1 or 2 pounds would be demoralising for me.
Instead, I weigh myself every 3 months, so that was a real boost at the first weigh in, to find I'd lost over 1 stone.
I continue to walk daily.
I think that we're all mainly creatures of habit so it is just a question of recognising and identifying your own habits that have led to weight gain and then swapping some/all of these for habits which will help you lose weight and maintain that weight loss.
That's why a diet or regime that works for one person won't necessarily work for someone else.
Good luck.
It does feel fabulous once achieved and the energy gained is phenomenal.