I-864 Affidavit of Support - I need help and advice

[SoumyaR]

I lost my job last month. I received email from NVC to file affidavit of support, Since I am between jobs right now, how do I file form I-864, do i need a co-sponsor(have no family here).
I have little funds saved in my saving account. I am a US citizen. May I please request anyone to guide me.