I personally won't try a HV atty. I like the normal attie at 6v. If it gets too much, or washes out the flavor I'll use 3.7. To me getting a HV atty is just a 3.7v experience at 6 or 7.4 volts. This is just the way I see it, I am probably wrong.
I would recommend folks who are new to HV
vaping use an 801 at first, they are much more forgiving than a 510.
With that being said, the above advice is good, keep them wet, keep the draws short, and if you get even the slightest hint of burning flavor put it down for a few minutes before topping off. Also, with freshly charged batteries you are probably getting about 6.4-6.6 volts, be very careful until the batteries drop a little bit.