It looks like the Twist/Spinner recommendations are spot on- variable voltage options are now cheap and ubiquitous, and that kind of flexibility and control is good to have.
I want to stress, though, that the juice you get, and the nicotine content, is really important. The rough estimations I've seen put a regular ol' cigarette at 24mg. I STRONGLY urge you not to even think about getting a juice beneath that. If you do what I did, and try to cut down your nic intake drastically and right-away, you're going to be cranky and disappointed in vaping because it's not satisfying your cravings.
Also, what Kopfstimmen said: You may have to supplement your vaping with smoking at first. THIS IS OKAY. Every cigarette you DON'T smoke is a victory.
Adelwolf is correct in that you need a juice that is strong enough to hit the cravings.
I would add that you also need to vape before the cravings start...
First thing in the morning vape, anytime you would have taken a smoke break-vape...like after a meal or driving to work.
You are training your brain that if you allow it to receive the nic through Vaping instead of smoking- and you will not deprive it of the nic it needs...your brain will not wig out on you that it needs a ciggy. Vape before you need it. Vape longer than you smoked a ciggy.
Also...drink lots and lots of water...the PG/VG drys you out, and the extra water flushes the ciggy toxins out of your system...another cause of withdrawal symptoms you won't experience if you drink plenty !
If you crave a ciggy...vape, then vape again. If you still want that cig...go ahead and have it, it's ok.
Might be you need a stronger ejuice, or you waited too long before you vaped first.
That's why I said you need to vape before you 'know' you need to vape....nip it in the bud !
Glad you joined us here...
Best to You !