Aubameyang's brace and Alex Iwobi's stoppage-time effort guided Unai Emery's men back to winning ways in Saturday's Premier League fixture after defeats to Southampton and Tottenham Hotspur in the past week.
Aubameyang opened the scoring at the Emirates in the 14th minute by finishing off a beautiful team-work that involved 18 passes in the build-up.
He later doubled the lead with a fierce effort that left Joe Hart helpless three minutes into the second half.
And the 29-year-old disclosed how he worked on that exact finishing in training on Friday.
"On the first one I just tried to be faster than the defender. I tried to shoot at goal," Aubameyang told club website.
"For the second one, we worked on this, in front of goal, and this was like yesterday (in training). The first touch was good, the control is important, then you just shoot and try to score!
Iwobi who was introduced for Alexandre Lacazette wrapped up the win with his second league goal of the season.
Aubameyang's brace on Saturday took him back to the summit of the scorers’ chart with 12 goals so far - one ahead of closest rival Mohamed Salah.
But the forward is anticipating a 'long' ride on his mission to dethrone the Liverpool star who won the top scorer's award last term with 32 goals.
"I think it's cool, and it's good to know, but now I'm just looking forward because the season is still long," he added.