Pickup some menthol drops, and go very light like 1/2 drop or 1 drop to say 15ml's of any juice you want to make mentholated. Alienvisions dot com has some good ones and I'm sure other vendors do to but I use the Ave drops and like em. You can go a step further and buy the crystals and dilute them and make your own DIY Menthol drops if you want to. Either way you go you can then make your own menthol solution by sweetening this , adding a drop of spearmint, lemon, lime, whatever you want, easy peezy and just works. Trick is what you add to the menthol, and go very light adding to the juice a little goes a very long way.