I've decided I need to do the 500 cals days when not at work. My work can be quite demanding as I'm a support worker so can go from sitting around to walking 7 miles (some hilly). I can rest more at home ignore chores. 
I've only started today and have had a very small breakfast of red berries special K, semi skimmed milk. For lunch I've had salad with mussels, no dressing just lemon and a pinch of salt. I've had black coffee with sweetener and water to drink.
I think I have 100 cals left so may have some homemade soup later? Only made from veg though. No fat.
I've had a good walk today with the dog but only a couple of miles. Some of it hilly. I haven't overdone it though.
I think I can cope with this lifestyle change. I love veg and salads. I can adapt the meals for dcs and dp wants to lose weight too so he may do the 5:2 but probably on different days. He has a sedentary job so said he'll do it on work days.
How's everyone else getting on? A few people I know have lost amazing amounts of weight but look great with it. Not lethargic like some do when trying to lose weight.