I'm just now beginning to purchase 0 nic juice after working my way down from 24mg-ish. I spent my first 6 months with the 24mg, and dropped about 3mg every couple of months. The 3mg transitions were hardly noticeable until I went down to 0 nic (6mg is the lowest my local b&m offers aside from 0 nic). The transition from 6mg-0mg was a little rough, so I kept a 30mL of 6mg around juuust in case. Usually just dripping once or twice was enough to trick me into chilling the eff out about it.
Take it slow, and don't beat yourself up about it if you need to grab a higher strength juice every once in a while. Good luck! The reduction in throat irritation alone has made it worth it in my opinion.