I'll go through the same song and dance with you that my friend did with me (he owns the vape shop down the street from me and participates in annual competitions, so he really knows his stuff, at least as far as I know), mostly because I don't want to hear about you getting badly burned (or worse) when your batteries go belly-up on you because you didn't build properly. Accidents DO happen.
Let me start off by saying that as a rule of thumb, you don't want to go too low on the resistance when starting out. Most box mods these days are regulated so the batteries are unlikely to vent, but the chances of this happening definitely are not zero, so it's always safest to treat every mod as a non-regulated device. I suggest keeping your coils above 0.25 ohms, at least until you get the hang of Ohm's Law and how it applies to battery safety when vaping. I have seen some pretty horrific injuries on people who have overdriven their batteries, though like I said before, this mostly happens with non-regulated devices such as mech mods, hence you want to stay away from those until you become more experienced. Your box will likely have safety features built in that won't allow the mod to fire if the resistance is too low. You will get a message like "Atomizer too low."
Also, another safety tip: Don't use batteries that are peeling on the top or bottom terminals. Have such batteries rewrapped. Most vapor stores will do it for you for little to no cost. My local vape store charges 2 bucks per battery for a rewrap, but stores vary. I'm not talking about a bit of buckling. That's fine. I'm talking about tearing to the point where metal is showing.
One last word of warning: I know the TFV8 - my mom has one. That tank will leak like a sieve if you don't thread your cotton correctly. We eventually gave up on the rebuildable portion of it and just went with the stock coils. That's the main reason why I cannot stand rebuilding on a TFV8, and will NEVER recommend it to beginners. But if you can get past that, it really is a great tank. I'm sure there are people here that have had far better luck than I had with it. I don't know if my mom just got a bad deck with it (because the tank works damn good) or I'm just a total newb with it. It's more than likely the latter, and I'm hoping someone will come forward in this thread to explain more about rebuilding on the RDA deck of a TFV8 because I *really* want to buy this tank, but I don't want to be stuck paying 15 bucks a pop for 3 coils for it. That's why I always vape on a rebuildable - you save a crap ton of money on coils, and all you really have to worry about is juice, cotton, wire and possibly a new deck or box when you decide your existing deck no longer does it for you or your box kicks the bucket.
With that out of the way, I suggest you use the CoilMaster V3 kit to wrap your coils, at least until you get the hang of hand-wrapping. The kit is really the easiest way to get started if you want to be able to just hook up your coils, wick 'em and go to town, plus it comes with an ohm meter so you can fine-tune your coils to get the desired resistance. The more wraps you have in your coil, the higher your resistance will be. You can also target specific resistances, but I'm not advanced enough for that quite yet.
This is the CoilMaster V3. It's 50 bucks, and well worth the investment in my opinion. This is basically the same kit I learned with, except I had the V2, which didn't have the little button on the ohm meter that test-fires your coils, so the V3 is a little more convenient in that you don't have to attach your tank to the box to test your new coils.
https://www.coil-master.net/product/coil-master-diy-kit-v3
You pretty much know how to hook your coil into your atomizer, so I won't get into that. The next step is to pulse the coil. That means pressing the fire button just until the coil starts to glow red hot. You want to try to get your coils to heat as evenly as possible. If they're not heating evenly, use the ceramic tweezers that come with the kit to kinda jimmy the coils around, pulse the coil again and repeat until you can get your coils to heat evenly, starting from the center and spreading outward. If you choose not to buy the kit and instead choose to hand-wrap your coils, you might have to heat the coil, use a small pair of pliers to get the coil wraps closer together, then use a small screwdriver to jimmy the coils into position.
From there, wick and juice your cotton (you want to get your cotton saturated, but not to the point where it starts dripping into your juice well), then start your box at about 20 watts and vape on it. If it doesn't satisfy you, turn up the wattage a little at a time until you hit your "sweet spot." Each coil will likely have a different sweet spot when you first start out, and this is the best way I have found to fine-tune your mod until you get the strength you want. Once you gain experience with making your coils, you'll be able to more precisely tune your coil to get the desired strength.
One more thing: When you first begin vaping on your new coil, you may/may not get a taste of new cotton. It will likely taste pretty disgusting at first. That's normal. That is simply because the cotton is new, and the juice hasn't had a chance to really get into all the nooks and crannies in your cotton. Re-juicing after a few minutes will likely get rid of the new cotton taste. There's also supposedly certain brands of cotton out there (Cotton Candy is one, but I don't know of any others) that make the cotton in such a way that the new cotton taste isn't as noticeable. You might want to do a Google search to find out which brand of cotton will be best for you.
Last but not least, if you ever get a message like "Atomizer short", try repositioning your coils. Failing that, wiping excess juice off your tank and mod will usually fix this problem. Sometimes your tank will leak and excess juice will get inside that hole I mentioned earlier, causing that message to appear. If all else fails, try removing your tank, click your fire button a couple times to reset it, causing your box to display a "No atomizer" message, then reattach your tank.
Apologies for the huge wall of text.
