Don't mean to offend anyone; but as this is the new members form, (all) please understand the fundamentals and potential danger regarding RBA's, especially concerning sun-one-ohm vaping.
The last thing our community need is negative publicity.
that out of the way:
own a good multimeter
Understand Ohm's Law
(for a dual coil) check the resistance of each coil pre-installed.
Check the resistance of your coils(s) installed.
Pulse your build as you check and brush your coils.
And do not trust YouTube to build you a safe coil.
Air flow, to a point, is directly proportional to vapor production; however, air flow is also inversely proportional to flavor. It's simple, in its dichotomy; how much do you want to stoke your coil vs. how much air do you want to mix with your vape.
Any system is as weak as it's weakest link. A mech mod's weakest link Should be the battery use. Sub-ohm coils require explicit knowledge regarding the C rating of batteries and more specifically the maximum continuous current output of you battery.
AW's 18350's should not be pushed harder then 6 amps.
The new-ish Orbtronic 18650's have a continuous rating of 10 and a pulse (~10 sec [?]) rating of 18 amps.
If you're under or over wicking change your resistance, change your wicking materia or build.
Bore your air holes gradually to meet your build, unless you know what you after.
Stock Nimbus air holes require a build of ~2.4 ohm coils on each side, and at that resistance your battery on a mech sill be 'done' at ~ 3.6v, rather than ~3.2v at ~0.8 ohms. Quite diffident vape and a difference in vape time actually.
And that is just scratching the surface.
This is why some shops, shamelessly, charge for builds. I say each will find their own, it will take some time; and RBA's aren't for everyone. Now-days some clearoz actually work..