xplorer² window can be quite complex as you can see if you start turning on the auxiliary panes available from View menu. You can have a folder tree, a previewer, details pane, various toolbars and so on. These can be moved around to the left or right, docked one next to the other and have various sizes. You can have dual panes arranged left/right or up/down, and even switch to single pane mode. It can take a lot of effort to bring the workspace to a comfortable state.
Like there is no one hat fit for all social and weather occasions, a single workspace will not be suitable for all your file management tasks. That's where Layouts come in play. You can save the window location and appearance as a workspace; you can have any number of them listed under Window menu, and switch among them as need be. Here's how you do it:
1. First setup the default layout which you use more often. Enable and disable the display elements you need and size and dock them to taste. That's how your xplorer² window will be like when you start the program
2. For different tasks create new layouts. For example you may need a media browsing mode, where you just need a very big preview pane. Arrange the window for the media task then use Window > Save layout menu to save the workspace with a name like "Media". To finalize (save) the layout close the window.
3.Whenever you need to switch layouts use Window > layout name menu command. This opens a new window. If you need to close the old layout there is a tickbox in Tools > Options, Advanced page that serves this purpose
Keep in mind that layouts deal with the window appearence but not its content. You cannot save the browsed folders as part of the layout (at least not in a consistent way). If you need to switch to particular folders then use command line arguments. You can also control which layout shows from the command line using /S:layout_name switch — but most of the time you start xplorer² in its default trim so /S: isn't necessary.