Part experience, part luck and you need to have the right mindset to do it. There are a lot of players who will never perform a run-through type bunkering as they're too scared of being shot.
I have a healthy aversion to pain so do it rarely, but when the red mist does descend occasionally I've had experiences at both ends of the scale. Some times I've started a move and promptly got lit up by 4 players simultaneously as I'd misread both the numbers of players still in play and where they were looking/shooting. On the other hand I've had the rare (as in once) success of going from my 40 to the other end of the field in one move, taking 4 players out en route - as they were all looking out the wrong side of their bunkers at the time or otherwise engaged.
Only cues you tend to get are comms from your teammates on where opponents are, sight/sound/feel of paint being shot in your general direction and your own view of the field to see where people are or where they ran to on the break.
I was lucky that my one piece of luck back in 2008 was captured on camera for me to bore you all with for eternity:
Start point - 30 or 40 line bunker which I made from the break.
No-one seems to be looking my way so off I go, gun up and firing at a bunker I know someone is behind:
Lucky break #1 - the left tape player is potting up with his gun down, kill #1
Lucky break #2 - Lemon is out the left of her bunker, kill #2
Lucky break #3 - Back left player not looking my way, ignore him for a mo
....as I'm sure there's someone else back here, aha!
Lucky break #4 - Back centre player looking out left.
Ptew! Kill #3
Catch up with the back left man now, ptew! Kill #4
In my case, 95% luck, 5% skill. My top bunkering tip would be - don't overdo the paint lovin'. People don't mind getting bunkered provided you don't hose them down. One in the back and one in the pack is always a good motto.......oh and don't start a move with an empty hopper, that sucks.
At the end of the day it doesn't matter how good or experienced you are, if you're unlucky and someone switches side just as you start running, it's time to count your welts in the deadbox.
