I) 0-5 minutes: Farm.
II) 5-10 minutes: Recall once you have enough cash dollar for avarice blade, TP back to lane. Farm.
III) 10-20 minutes: Farm until you have enough for sheen and chalice.
IIII) 20+ minutes: Farm to victory, equation for required amount of farm = 2Q (where Q = the amount of farm held by your mid-laner)

Pro tips:

Show the schumks and their spiel about how gangplank is a goy to be farkakt by following these awesome 10 commandments

1)Your Q should only be used on enemy minions and neutral camp monsters
2)Never attack your lane opponent, it wastes time that could be used earning cash
3)Your ulti is most effective when being fired at another lanes farm
4)Your ulti gives instant assists
5)Use your E whenever you are near a teamfight to gain assists (This is ALL the participation that is required)
6)Use your taunt often to degrade the enemies morale
7)Use your heal, to heal (only yourself, of course)
8)Stockpile as much cash lategame as possible, your team mates are never deserving of farm
9)Waste your money on useless things to show your decadence, like wards
10)Aquire money

Follow this tips to make yo' mother extremely Kvel.

Appropriate songs to play on repeat as the Plank:

http://www.youtube.com/watch?v=waW6gnA2t-I (For everyday money making)

http://www.youtube.com/watch?v=yHhuQoQSiBg (When a full build has been achieved)

Pros:
-Gangplank wasn't circumcised, he was circum-navigated
-The Balebustes love his face fuzz
-Equipped for maximum cash production
-Movement speed
-Taunting your foes
-That Laugh
-A wide array of fantastic skins (the sailor skin being a must for all fans of 1970s disco)
-Plunder some Booty (yarr harr)

Cons:
???

All champions:
Difficulty rating = 1/10
Simply outfarm your opponent and drown them in money.

Nasus:
Difficulty rating = 0/10
Nasus will passively farm, just like you. Unfortunately for him you will outscale.

Another Gangplank:
Difficulty rating = 10/10
This is a true test of skill, which schlumk can farm the hardest?

Chairman Mao:
谁是我们的敌人？谁是我们的朋友？这个问题是革命的首要问题。

Nelson mandela:
“I learned that courage was not the absence of fear, but the triumph over it. The brave man is not he who does not feel afraid, but he who conquers that fear.”

Gandhi:
Live as if you were to die tomorrow. Learn as if you were to live forever.

Stalin:
When we hang the capitalists they will sell us the rope we use.

Captain Jack Sparrow:
Savvy?