I am no DIY guru... in fact, I am horrible ;-)
BUT, menthol is the easiest... so easy, even I can make it.
Let me share this with you... and you can have killer menthol and save big bucks... perhaps even survive the vaping apocalypse that may come this fall.
1. get a good nic base... I suggest Xtremevaping... like $13 for 60mls of 36mg...
(you can get it for even less at wizard labs or rts... I just like cleaner better nic - besides, it's cheap enough)
2. I like 18mg... so I add 60mls of pg to my 60 mls of base... (orVG) -
(now I have 120mls of 18mg base... cost me $18 or so.)
3. I think the best menthol flavoring comes from Decadent Vapors... mentholyptus... $4.67 for 10mls... 7-10 drops per 10mls makes it good and strong.
(or you can get any flavoring from anywhere)
it's that easy - and it's tasty... menthol is easy...
tfa and other companies have less expensive flavorings that are good too.