All dialogs are available from the Window > Default tray drop-down menu. You can collapse any dialog by clicking on the window heading. Typically, it is best to keep open only the dialogs that you need regularly, such as Entity Info, Materials, Components, Styles, Layers, Scenes, and Shadows. The other dialogs are not used as often, so it is fine to open them on an as-needed basis.
You can pin the default tray so that it automatically collapses when not in use. I don’t like this option because I have to hover on the tab to get it to appear again. This takes just long enough to be a nuisance.
I prefer to hide all the dialogs at once by clicking on the Window > Default Tray drop-down menu and choosing Hide Tray. Unhide them by going to the same menu and choosing Show Tray. Consider adding a keyboard shortcut for hiding the tray.
DIG DEEPER… Check out page 133 in “The SketchUp Workflow for Architecture”.
HEADS UP! SketchUp’s tray system is only available on the PC version.