A stone in a month is an awful lot to lose. Since you're setting yourself a time limit, you're probably better off following a healthy diet and exercising and seeing how much you do lose, rather than setting yourself targets. Crash diets are a no-no. You'll just put the weight back on.
A couple of golden rules for you: do some kind of exercise every day, drink at least 2l of water each day and don't snack between meals.
If you're looking for some information on healthy diets to follow and such, just say and I'll look some up for you.
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drinking till the daylight hurts
you seem friendly who are you
that's a lot of wine that we got through