Best family planning method is one which suits you and only you. There are loops and condoms; there are pills and injections, there are surgery for vas and fallopian tubes.
But none is one hundred percent. There are few less effective, there are few less costly you select your method only after consulting your doctors. No newspaper ad or TV ad be deciding factor. It may harm. As you are not saint, don't deserve nirvana; abstinence should come last in your mind. Enjoy life!