Overall, most of the information is good, but the guide could really use some cosmetic improvement, as it's entirely composed of text.

A few things to note:
-You should include alternate build paths and itemization choices. No champion is ever limited to one set of items.
-I would normally get 2-3 points into Pale Cascade before maxing Crescent Strike. It offers more damage and you don't need the extra shield during jungle clear that's leftover as a result of getting too many points into Pale Cascade early.
- Moonfall isn't exactly needed at lv 4. It might be nice to have if there's an engage but it slows your clear speed. Most of the time you will just find yourself farming to 6.
-Depending on the enemy jungler, you sometimes might want to skip wolves/wraith and jump directly to wraith/wolf in prevent the enemy counterjungling your secondary buff.
-For masteries I would recommend Fury over Sorcery

Good guide, I'm using it. Thanks for the tips. (:
haven't played Diana in a while.