It’s quite funny, Bethesda started a wiki over at creationkit.com for all Skyrim modders, but fail to mention where modders can get the creation kit. Never take anything for granted!
1. Step Open up Steam and click on View
2. Step Click on Tools
3. Step Now scroll down until you find Creation Kit, right-click it and click Install Game
4. Step Yes, they did not label it Skyrim Creation Kit, just Creation Kit
5. Step Now install it and you’re good to go
6. Step You should now head over to the Skyrim modding wiki and read some tutorials to better understand how to create mods for Skyrim