Getorf is really giving the best advice (not the exante bit 
You don't need to eat diet foods or weigh stuff out,just make sensible chices for permenant lifestyle changes,refined carbs,our snack/junk mentality and alcohol are the biggest reasons why we as a nation are hugely overweight compared to other countries (and yes I realise this is a generalisation)
and move more,whenever and wherever don't make excuses about why you can't exercise just do it.
I have struggled with my weight for the 1st time ever in the last 18 months,yes my thyroid failed so that could account for some of it but in the cold hard light of day I had been using junk food and alcohol to cover up my general unhappiness in life.So I am making changes back to where I was 18 months ago and voila,4 nights last week of not drinking,eating what I wanted when I was hungry and not because it was a particular time,eating smaller portion sizes of "normal" food,stopping when full,have not been able to exercise too much as half term and I have lost 2llbs,not a huge amount I grant you but I have had cake for mothers birthday and cheese and all normal foods.It will take a couple of weeks for my stomach to shrink slightly, to realise it does not need big portions,just normal sized ones.
I only get on my high horse about this as my dm yo-yo dieted throughout my entire life,she gave me real issues with food,I have been borderline anorexic at times and now she can't keep any weight off or eat hardly anything as she has completely (scuse my french) fucked up her metabolism,she is 70 next birthday and she dieted from the age of 19 :(