This is my first attempt at a guide, I will attempt to include as many different methods of roleplaying a dwarf - And there are many, trust me - In this guide.

1) Introduction
2) The Bronzebeard Clan
3) The Wildhammer Clan
4) The Dark Iron Clan
5) Dwarves and the Horde
6) Dwarves and the Alliance

Introduction:

I will start off by quoting this, from WoWwiki, drawn from the RPG:

"Dwarves are short and stout creatures mostly inhabiting Khaz Modan in the Eastern Kingdoms. They are shorter than humans but taller than gnomes, taking advantage of their size when possible and relying on their robustness and strength when not. The average dwarf is steady, observant and composed both during work and combat, yet able to rage with fierce zeal and persistence when the situation calls for it. While a dwarf prefers to plan forward to overcome challenges, many of them easily lose their temperament and self-restraint when exposed to conditions stirring their feelings and concerns.

In past ages, the dwarves rarely left the safety of their mountain fortresses, spending their time on refining metal and stone into powerful weapons and beautiful jewelry. However, when the call to battle sounded, they rose up to defend their friends and allies with unmatched courage and valor. dwarves like drinking, Mining, finding treasure. But the things the dwarves are most interested about is them and their past with the Titans."

As we can see already, dwarves in World of Warcraft are different to dwarves in other fantasy settings. They are not dying out and they are not obsessed with mining and blacksmithing even if they are still good at it. Also, by being called 'dwarves' and not 'dwarfs'.

We can also see that dwarves are not so obsessed with beer that they drink it even when fighting. Beer is an alcoholic. Alcohol effects dwarves the same way it effects humans, it does not make them stronger and more aware. So drop that now. A dwarf is composed and intellectual, they live longer than humans, meaning they can learn more.

In the regards to magic: At no point in World of Warcraft has it been stated that dwarves hate magic like they do in other fantasy settings. They have lived with their gnomish cousins for many years, after all. They of course detest demons with a passion like any Alliance race.

In regards to the accent: It does not matter, humans have many accents also, it is quite possible for dwarves to have varying accents. I will take Thunderbraid as an example - He is highly educated from the upper rings of Ironforge, and if we look at a good example of this - Senator Barin Redstone - His quest text does not contain any accent what-so-ever. Similary there will be more 'common' dwarves, and they will have the stereotypical accent, however, there is no need to overdo this accent if you do not wish to, if you read the quest text of dwarf NPCs, it is not unreadable. There is the occasional 'ye' and others like it, but little else.

It is possible to roleplay a dwarf without ruining your immersion by not using an accent.

(May be updated!)