This is a decent start to a guide. For starters, the usual order of guide topics goes something like Intro (describing yourself), Pros/Cons, Masteries/Summoner spells, Runes, Items, Laning phase, counter/lane partners, summary/conclusion.

It also looks like you're cropping images instead of using BBC coding. Typing [icon=jinx] would give you , for example, and same for items ( ) and runes.

Another thing is that you use big letters so that it looks like you're saying a lot, while in retrospect, you're not really saying much about the champion. To improve on this, go more in depth with why you think certain things are good/bad, why are the stats better, why are those mid laners hard to lane against, and a bunch of other questions.

Don't contradict yourself! Your title says Jinx The Most Versatile Champion, and in the guide you say she's Great at Peeling, but later you say she has low mobility and easily disposed by gap closers?

Check through your guide for spelling/grammar errors, and look at top rated guides for ideas/inspiration (but don't copy them).