During work with photoshop on a specific area of a picture - pres SPACE button. Cursor will change in hand tool. Holding pressed SPACE - press LMB and move picture lika a sheet of paper. After releasing SPACE - you will back to previously using toll.
This option also works in other photoshop tools - Filters Liquify, Save for Web and others where we can see picture preview.
To zoom in or zoom out size of using tool (brush head, stamp etc.) - use keys [ and ]. Left makes tool smaller, right - bigger.
If you have lots of free RAM memory - you can increase number of saved steps in a history panel. History
To make it choose: Edit » Preferences » General or press buttons Ctrl + K.
In window which will appear - change value in field History States and press OK.
To hide all visible bookmarks and Toolbox - press Tab key.
To hide all visible panels exluding Toolbox - press Shift + Tab keys.
To return to default view - press previously pressed keys.
To remove, cancel selection picture area - press Ctrl + D.
To easy and precisely change value in any field - click LMB on that field and roll mouseroller to change value one more or less.
This method also works in lots of rolled menus where instead of numbers are text fields. Rolling effect we can se live on a editing picture.