Consider the following;
Remember! You need a higher priority to get the items you want!
Angerona and RagingDaddy are raiding! 2 manning a raid that we apply our EPGP towards. This is what the current situation looks like;


As you can see, Angerona has 170 Effort Points, and 100 Gear Points.
Effort Points / Gear Points = Priority For An Item
EP/GP = PR
170/100 = 1.7
Angeronas Priority for the item is 1.7.
RagingDaddy has 100 Effort Points, and 100 Gear Points.
Effort Points / Gear Points = Priority For An Item
EP/GP = PR
100/100 = 1.0
RagingDaddy’s Priority for the item is 1.0
Alas! Legplates of Relentless OnSlaught drops!
Seeing as how RagingDaddy is an awesome Arms Warrior, and Angeronas Retribution skills are unequalled by anyone, outside of the Paladin class, they both express an interest in the item!
Once the Loot Master declares the item in raid, we both say that we would like to roll on this item by informing the raid. A (/roll 1-1) is the easiest way to do this.
Because Angerona has a higher priority than RagingDaddy, the Loot Master assigns the item to her.
The number with the red box around it, is the Gear Point Value of the item. More-desired items have a higher GP wort, this item has a GP value of 165.
When the Loot Master distributes the item, the EPGP addon also changes the values in the officer notes, where they are stored as variables.


After the loot and GP distribution;
Angerona has a new priority of .6415.
Meaning the next item that both parties are interested in, would automatically go to RagingDaddy, as he has a higher priority.
I hope this give you an indication of how EP/GP works, this addon acreen can be seen after downloading the addon itself from the website.
If you have any other questions, feel free to ask in-game. If these are helpful examples, we can expand on other functionality of EPGP that we will use.