League of Legends (LoL) Question: How do you open your saved guides?

The easiest method of opening saved guides is by clicking on top-right your screen where your nickname is. After that, go to "Content Library", which is below your profile image. After that, click on the filters option in the right, and set it to "All Guides". Your saved guide should be there.
Best of lucks!

Once you're on the page of a guide that you own, the top left of the page should say "Champion Build Guide by Mysteriousness", followed by a picture of your avatar and a bunch of other things. Right under your avatar is the button "EDIT". Clicking that button will lead you to being able to edit your guide.

:)