*wave* im new....dont no where to start??

[SJM]

hi im sammy, i could with a bit of advice...i dont know the first thing about dieting, im not sure if i need to go on a diet or just excercise, or maybe both, iv never understood??i might sound a bit stupid but let me explain what im after...... the thing is i wouldnt really say im fat, im a size 12 and maybe a bit out of shape,i used to be a 8-10 and loved being that size, i could pretty much wear what i wanted to wear....but now i feel like my belly and (back fat) hang over my jeans and i always have to wear baggy jumpers/tshirt to cover it up....i would love to be able to wear nice skimpy tops for the summer, so my goal is to have a flat belly and toned leg,bum & tum for the summer.... i am starting to lose alot of confidence and i used to be really out going and a very high maintance person, and now im jus starting to let my self go....i dont feel very sexy around my boyfriend and im always complaining, he says im fine, but i think he just says that.... do you think maybe just lowering my meal portions and only snacking on fruit and also 30 mins excercise a day will do the trick and help me reach my goal? thankyou