Keep off weights for legs and opt for lunges and squats instead. For the arms use as heavy a weight as you can and do 10-12 lifts with three repetitions for near immediate results. Sit-ups flatten the tummy. 30- 50 is ideal, though remember it is quality not quantity that counts. Instead of eating snacks like cake and crisps you should go for fruit, nuts and sunflower seeds.
Sugar produces a surge if insulin encouraging the body to store fat.
Try and stick to this regime and not only will you look good but also feel fitter and healthier.