You can use coding instead of adding pictures when talking about abilities, items, masteries etc.
Just make use of stuff like this:

by writing [icon=Onslaught of Shadows size=60]

For example when you talk about Masteries you spend way too much area for this section so you might think of changing this. Besides, your Rune pictures are not for Tier 3 Runes so just use the icon stuff with the Rune name :)

After this go on finishing the guide's content by talking about Gameplay and jungling ... :3

Good Luck!

I like the jungle build,
anyone could tell you that you need colors, but me, I'm gonna tell you to fix the spacing in the Items chapter :)