I quit a 1.5 pack/day habit in one day when I received my Halo G6 starter kit.I really don't know how people can go from a pack a day to ecigs just like that.
Having only vaped for five months, I still consider myself to be new to all this. But from what I've learned and experienced so far, I think the key is finding (1) an e-juice that you will really like and (2) a good quality vaping device that provides the features you need to get good results from the vaporization of the e-juice.
It's all about the vapor that goes into your mouth. The flavor, the temperature, the throat hit, the density of the vapor and the amount of nicotine in it.
I was a Salem Light (menthol) smoker, so I got a 24mg menthol sample pack from Halo, and found that I really liked a mix of 95% Menthol Ice and 5% SubZero. Now I use MBV's Black Ice 18mg juice most of the time, but I still use my Halo mixture every now and then.
I don't know how to make another person want to quit smoking. All I can do is relate my own experience doing it.
I would recommend getting a simple, adjustable voltage eGo device, a couple of Kanger T2 tanks for it with medium resistance coils (2.2Ω or 2.5Ω), and a sampler pack of e-liquids from an online merchant that you see mentioned often here on ECF. Halo is very good. Mt. Baker Vapor is very good. Ahlusion and Nicoticket I haven't tried, but many here hold them in high regard.
Better yet, find a B&M (a physical store) in your town that will let you taste-test e-liquids onsite, so you can hopefully find one or two you like before having to buy anything at all.
But as cbrite says, you have to WANT to quit smoking strongly enough to be successful at it.