I would say:
Step 1: clip the area, never had to "shave" to skin. Worked fine for over 3000 cows and countless horses over time
Step 2: have someone that knows what they are doing.
I have seen some messy messy brands over time (just about unreadable, due to the 20 second rule with the animal moving from sting) We were lucky that our Farrier was also a brander and we got him to do our horses and cattle (dairy) you want it nice and neat. Never used isopro. Again all of the above have been fine.
I would not really go by those instructions, would not class them as 100% correct. Find someone that does it alot and and slowly learn from them.