Gift deed

Sir I have a flat in Surat Gujarat I want to gift it to my aunty real sister of my mother. Do should I make a sale deed or gift deed so that officaly the property will be transferred to my aunty name and I want to save tax and money on registration so what is the possible ways in which with out any hurdle I can give property to my aunty. So sale deed or gift deed is better option . And another question is gift deed legal in Surat gujarat