Plz help to submit form 15 g

Sir plz help me in submitting Form 15G. Is form 15G has to be signed by any CA or any authority or we can directly fil it by downloading form and submit it to banks. Plz clarify me sir my father got an intimation from bank to submit Form 15G in order to avoid TDS deduction. But we stay at a village where we dont have CA's at our place we have to travel other place for CA. Hence kindly guide me whether we compulssorily equire a CA for submission of Form 15G? sir Plz plz... give possible guidlines in this regard as early as possible..