I don't know what the best way to leave is. I do know there are lots of ways to leave. I do NOT recommend that you leave the way I did, but I'll tell how I left anyway.
I got married at 23. I love my wife, but obviously wasn't as committed as I should have been. Without going into much detail I committed adultery, which I think most people would consider bad whether you're JW or not. In the meantime, before and after that happened, my mind had been slowly questioning certain things. Philosophy classes I had taken a couple of years before my indiscretion had been pestering my mind. I seriously revisited the question of whether there was a God and came to the conclusion that all my life I had only listened to pro-God arguments given by the JW religion. And even based on their evidence alone, I had no conclusive proof that there is a God. I understand some people believe in faith and don't need conclusive proof. The evidence for God is enough for them even in the face of the evidence against God. But for me there was no conclusive proof either way. Since I couldn't believe in God, based on my thoughts and observations, I couldn't believe in the religion. After I opened up my mind to that, blinders started to come off regarding other things like the so-called God given authority of the faithful and discreet slave and the generation teaching. The floodgates were open. I came to the conclusion that I didn't care to stay in the religion.
I have family who I care for and I knew I'd regret losing contact with them. I did have some friendships in the congregation but none too strong. I decided that I'd didn't care to do the fade or put up some sort of facade in order to maintain these contacts. There's 6 billion people in the world. I can make some new contacts. I confessed my adultery and said I was unrepentant just to get out. I know a selfish reason to confess. I did tell my wife first. It took about a month after I confessed for them to finally DF me, but that was it. They tried to get me to come to two or three different judicial committee meetings. I caved and came to their last one which was sort of a formality. They didn't even open their Bibles. They asked me maybe 2 or 3 questions, none specific about the act, because I'd already made it clear over the phone that I wouldn't be answering any questions about that. They sent me into this other room for 2 minutes while they made their obvious decision.
Haven't been bothered by them since. During the course of this happening, I talked with my parents a few times. My dad had a few conversations with me. But after I was disfellowshipped, they don't try to talk to me about the Bible. JW rules say they aren't supposed to. I've been fortunate to have parents with a little heart. They break their JW rules and talk to me some but not about religion. Contact has been broken with my three JW sisters. I have a younger brother who has told me he plans to get baptized, but he still talks to me. Actually we've talked more now than when we were growing up. And strangest of all, he just married a non-JW girl who stayed with him a few weeks before they were married. So doesn't look like he's toeing the JW line if he plans to get baptized. Maybe there's hope for him. I don't try to steer him the right way. He'd never listen to me anyway.
So to summarize, I guess a person has to know their family and friends to determine what the impact will be on those relationships. Everybody has to leave their own way, but I am glad I was able to leave quickly. My wife and I are together and working on things. If I had not made that mistake, I think I would have disassociated myself. Slow fade isn't my style. If you want to do it quick, you just have to be firm with them. Write you disassociation and refuse to communicate with them. Don't answer any questions. Don't allow them to come into your house for an attempt to "readjust you", unless you think it would be fun to debate them (I've seen some people who had interesting stories about that). Of course, I've heard of some who employ similar techniques with the fade. I think its about realizing whose in control of your life. It was a very exhilirating feeling when I finally realized, that I don't have to recognize the authority of elders or any part of the JW organization.