I don't do anything differently at 47 as I did at 27.
I can go hard and fast as I usually only have half a stone to lose (I gain it by not paying attention, usually over the course of a year).
I do 1200 cals, count everything except salad (leaves, cherry tomatoes, veg like cabbage etc).
I get a lot of protein from Fage fat free Greek yoghurt plus biotful do a plain protein quark kefir which is amazing with blueberries for breakfast and is 30g protein.
I eat a lot of prawns, plain fish, sashimi if I'm in London for something or travelling. As an example for eating out, I did a diet last summer and we had to eat at one of the Ivy chain restaurants, I chose the fish, avoided the break, had fizzy water to drink and a coffee for pudding.
I usually build in once slice of sourdough to have in the evening with 40g of avocado and an egg for dinner. (we all eat differently due to DS with ASD, so it's not weird that we don't eat dinner together here!)
Lots of coffee helps, lots and lots of walking, plus I'm very fit anyway and do a lot of weights workouts each week. But definitely up the fast paced walking. If nothing else if you are walking you are not eating!