What is my view on writing accents? Don't do it.
Write normally. Everyone has an accent, but more often than not they are speaking the same words. There is of course the exceptions of slang and colloquialisms, but when it comes to general terms, do not go all out on apostrophes and skipping letters because you think it will equal an accent. It does not always come across to the reader as you hope it will.
For example, I once read a book set in Australia, where a written accent was chock full apostrophes. Not only was it hard to wrap my head around, but I had assumed that this was the author's attempt at writing a different Australian dialect. After a lengthy attempt at tripping over this character's dialogue, the author then explained that the speaker was meant to be Irish! I would have had a much easier time reading the passage if the author had written the character's speech normally, and just mentioned that they had an Irish accent.
If you don't believe me that a throwing apostrophes at words like ninja stars doesn't equal an accent, try writing one and ask a few of your peers to see if they can tell you which accent your character is speaking. With the exception of colloquialisms, they'll most likely be lost. Just because you're thinking of a specific accent, doesn't mean that it will automatically translate onto the page.
Not to mention that lacing words with unnecessary apostrophes can slow down the reader, which doesn't help with story progression. If the reader is frustrated, they aren't going to make much of an effort to tear through your book. You have to give the reader some credit and leave them to make the connection themselves without fill'n up all yer words wi' random apostr'phes an' misspellin's.
The better choice when trying to emphasise a character's speech is to use slang and colloquialisms. In New Zealand we call flip-flops "jandals." In Australia, they call them "thongs." There are always slang terms like "summat" instead of "something like that," and "hang out" or "chill out" instead of just "spend time." When writing a French character, you might slip in some words of the Welsh language into an English conversation, instead of spouting out any of ze cliché pronunciations.
Of course, I don't reprimand the occasional apostrophe instead of a letter. A little accented speech never hurt anyone, but don't pick a character who is outside the "norm" (which is slang, see what I did there?) and accent them until the reader wants to smite them...or you.