docs: update user guide (kubernetes#1882)

* docs: update user guide

#### What type of PR is this?

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Add one of the following kinds:
/kind bug
/kind cleanup
/kind feature
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/kind documentation

#### What this PR does / why we need it:

Updates the user guide completely revamp it / describe each label.

#### Which issue(s) this PR fixes:
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*Automatically closes linked issue when PR is merged.
Usage: `Fixes #<issue number>`, or `Fixes (paste link of issue)`.
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Closes kubernetes#1584
Closes kubernetes#1577

#### Special notes for your reviewer:
Signed-off-by: Charlie Drage <charlie@charliedrage.com>

Please check the docs examples / each label that it's okay!

* Update docs/user-guide.md

Co-authored-by: TessaIO <ahmedgrati1999@gmail.com>

* Update docs/user-guide.md

Co-authored-by: TessaIO <ahmedgrati1999@gmail.com>

* Update docs/user-guide.md

Co-authored-by: TessaIO <ahmedgrati1999@gmail.com>

* update capitalization

Signed-off-by: Charlie Drage <charlie@charliedrage.com>

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Signed-off-by: Charlie Drage <charlie@charliedrage.com>
Co-authored-by: TessaIO <ahmedgrati1999@gmail.com>