Also excellent points about a tidy work area, and having only one thing open at a time, then capping it and moving it aside when you're done with it; a further point would be, go down your recipe in order as printed, to reduce potential confusion about what you've added -- hence the moving-aside of the flavors as you finish with them.
Obviously everyone has their own personal preference on order. Personally I always start with the nic base, then add the flavorings, then the VG, and last of all the PG. I follow this order partially because in my mind the flavors and nic are easier to mix when they're at the bottom and you pour the VG and PG on top of them. I don't know if there is really any truth to it, but it's what I do.
I also line things up in order before I start, and move them to the other side of the table after I've used each ingredient. That way I know exactly what I've already used.
Also, be sure that all the tools you need are available to hand, and any recipe items that are pre-mixed (such as ethyl maltol, though there are others) are already mixed, fully dissolved, and ready to use, before starting on the recipe; it saves a lot of confusion and potential mishaps.
Andria
Agreed.
And always remember to give your nic base and flavorings a good shaking before you use them. Both the nic base and flavorings will settle when left on the shelf so be sure to shake them up and get them mixed them really well before using them.