Polymorph can make it to where you cannot go invisible during a negative battle. Try to dodge her polymorph and get out of there unless you are higher leveled than her or if you are 2v1+.
Make sure to use your ult to get out of his ult if you don't have beads. If you do have beads, use the beads and safe your ult for later.
This isnt often, but sometimes when you are preparing for a gank, Nu Wa uses her ultimate, notifying of where you are on the enemy map. It isnt often that she does this at the right time.
His God Kit can shut you down easily. Unless Vulcan is low or has all of his abilities down, there is your time to strike. Make sure to stray away from his turret at all times.
Put your decoy down far enough behind the minions in the jungle for you to be able to use your passive efficiently. Don't use your 3 unless you are in a stressful situation.
Make sure to use your ult against fleeing enemies. Rarely leave the team unless you plan on ganking from behind for lets say a 3v3. If its a 5v5, never go for a gank unless you plan on cleaning up a fleeing opponent.