how do I add my Lightroom presets to the new Lightroom CC?

1. In Lightroom Classic, go to Edit menu (Windows) / Lightroom menu (Mac) > Preferences > Presets tab and click the Show Lightroom Presets Folder button to open an Explorer (Windows) / Finder (Mac) window in the right location, and copy the contents of the Develop Presets folder.

Alternatively, you can navigate to the hidden files at:

Windows—C:\ Users \ [your username] \ AppData \ Roaming \ Adobe \ Lightroom \ Develop Presets \

Mac—Macintosh HD / Users / [your username] / Library / Application Support / Adobe / Lightroom / Develop Presets /

then...

2. In Lightroom CC, open an Edit view, click the Presets button in the bottom right corner, click the + button at the top and select Show Presets Folder. Paste the presets into the Develop Presets folder.

Alternatively, you can navigate to the hidden files at:

Windows—C:\ Users \ [your username] \ AppData \ Roaming \ Adobe \ Lightroom CC \ Develop Presets \

Mac—Macintosh HD / Users / [your username] / Library / Application Support / Adobe / Lightroom CC / Develop Presets /

3. Restart Lightroom CC. 

To move your Lightroom Classic presets over to Lightroom CC, you can copy your presets from Lightroom Classic which are present 
Here for Mac:     ~/Library/Application Support/Adobe/Lightroom/Develop Presets/
Here for Windows:   C:/Users/{you}/AppData/Roaming/Adobe/Lightroom/Develop Presets/

And paste them to Lightroom CC
Here for Mac:    ~/Library/Application Support/Adobe/Lightroom CC/Develop Presets/
Here for Windows:    C:/Users/{you}/AppData/Roaming/Adobe/Lightroom CC/Develop Presets/

Restart Lightroom CC and they should be there!