The prayers of all the users who have asked for this feature for quite some time, have finally been heard by Valve and the they have been incorporated into the new Steam client.
Until recently, users relied on third-party tools to move their games, but may now use the Steam client for the same task. However, the feature requires more work, since to take advantage of it first it is necessary to add another installation path (if not any).
For this purpose it is necessary to resort to view > settings > downloads > Steam library folders > add folder in library and there select a path. When it is ready the new library, just right-click in a game to go to properties. The new “moving installation folder” option will be in the local files tab.
The new option to move Steam games available in the compilation of January 18. Check that you have installed this or a version more recent going to the menu help > about Steam.