I am trying to write a story about Twilight (from her perspective), and was wondering if you all had tips for writing in 1st person? And possibly a slightly split personality 1st person.

I dont really have any tips, but I can suggest reading this story which is in first person. Its really well done and would help.

First pony veiw

Try to avoid over-using "I" at the start of sentences... that is the primary complaint I get whenever I write a 1st person story.

If you are going for a split personality...

I would suggest that you utilize some form of differentiating betwixt selves, as it can quickly become very confusing if you don't.
"HAH!, No it isn't you just aren't thinking doing enough homework into the story!"
But, surely readers generally don't want to have to do work to read a story, would they?
"Forget that! They should beg you to write complicated and hard to read fics!
Well, allright me, I'll go with your plan this time, but only because you abuse the heck out of pony smilies!

870492
I don't use "I" that much (so far), but would the pronoun "we" be okay to use? Also, I never did think of making each voice different to read, only indenting new paragraphs to show it. You're idea is better.
870480
Reading this now.

870492

That kind of thing tends to get annoying after a while tho. I mean, 1st POV is already a close examination of your protagonist, so, having "split personalities" feels dumb.

870514

Also, learn the difference between "your" and "you're".

870753
I usually do... now I feel awkward.

870883

*hugs*

870753

I think you missed the point of my little Blurb. To have a character be schizo/split/mental/whatever, you have to either:

A) Completely alienate the reader by creating a character that the majority of the populous cannot connect to in any conceivable way due to an internal struggle beyond the comprehension of the common person.

or

B) Make your main character have a "Primary" personality. It might not be the one that is active most of the time, or the most plot-driving one, but it should be the one that is hopefully the most sane. By doing this, you inherently cause the other personalities to become completely seperate entities, however, you do stand a much better chance of giving the reader somepony to connect with.

On a personal note, I don't know that I can speak for the populous at large, but most folks that are willing enough to be open with me have admitted to, at some point in their life, doubting their sanity. Usually during their teenage years, or during times of great strife. The ability to truthfully doubt one's own perception of the universe is a terrifying window into the abyss that can slowly drive anyone mad. So be careful with what you write if you take this course.

But I digress, this entire argument is potentially invalidated by the fact that I might be misreading contextual clues, and you aren't writing a psychological fic.
Such is the woe-begotten life I lead whilst struggling to understand humanity as a whole due to my own neurological misprints.

870947
*hug*
Also, about the split personality, I was thinking of it only being the small extent canon Twilight has, at least in Lesson Zero. Poor mare snapped like a twig.

870514 If you happen to read the Dexter novels, they are written from a first person POV, so Dexter is always using "I" except when his dark alternate personality comes out, then the author slips into "we" and those scenes are really creepy and cool.

I see you're already set on Twi. But hear me out anyway.

If you're going to write a story in first person, you want to make sure that it's a character you understand very well. Just picking some character doesn't usually work out well.

And note that you don't always have to tall a first person story from the main character's POV. Look at Sherlock Holmes- the stories were obviously focused on Holmes, but Doyle told them from Watson's POV. (Mostly.) Why? possibly because he felt he would have a hard time portraying Holmes's personality accurately.