I would like to change how the mouse cursor (mouse pointer) looks.
I use Fedora 30.
Also, I would like to increase the cursor size.
Check what cursors are already installed by going to "Tweaks" app > Appearance > Cursor. If you don't have this app, install it:
dnf install gnome-tweak-tool
In my case, the only available cursor was "Adwaita".
Find more cursors:
dnf search cursor-theme
Install some of the ones you found:
dnf install breeze-cursor-theme oxygen-cursor-themes
Now go back to the "Tweaks" app and you will see more cursors to choose (you may have to close and reopen the app).
If the cursor is too small, you can increase it in "Universal Access" app > Cursor Size.
The change of cursor will take effect completely only after you restart Fedora. Without restart, in some places you will see the new cursor, and in others the old one.