When switching between open Apps in OS X, you might generally use Command-Tab; however, you can do similar switching, and far more, directly in the Dock. Even though the Dock is intended to be managed primarily with your mouse, Apple supports accessing it via the keyboard. The default action for this is to press Control-F3, but since some of its features are quite similar to Command-Tab, I recommend changing it to Option-Tab or something similar.
To do this, go to the Keyboard system preferences and then to the Keyboard section in the Shortcuts tab. Then click the Control-F3 shortcut next to “Move focus to the Dock” and give it a hotkey like Option-Tab (you cannot use Command-Tab). You can now use any of the following options for managing items the Dock:

Changing the Dock focus shortcut will make keyboard-access to it far more convenient. In this case, I have changed the shortcut to Option-Tab by clicking the default shortcut to select it for editing, and then pressing the desired hotkey.
Selecting and Opening Items
Use the left and right arrow keys (or Tab and Shift-Tab) to select the different items on the Dock, and then press Enter or the Space Bar to open them. You can also jump to an item by typing the first few letters of its name. One option here is to reveal the selected item in the Finder, by holding the Option key and pressing Enter. If you hold the Option key when pressing the Space bar, then the current application will be hidden when the new one is brought to the front.
Press the Up arrow key on a highlighted item to open its contextual menu, and then you can navigate the menu using the arrow keys, and then Enter or Space to select an item (this will not work on Stacks). Pressing the down arrow with no items in the menu selected will close the menu.
Note that you can also hold modifier keys before pressing the Up arrow, to reveal additional contextual options that might be available. For instance, doing so on the Finder will reveal the Relaunch option in its menu.
Moving Items
This may be a fun approach for some to try. Use arrows to select an item you want to move, and then hold the Option key. Now if you tap the right or left arrows, you will swap its place with the item to the left or right of it.

With an item highlighted, holding the Option key and then tapping left or right will move the item in the corresponding direction.
Quitting Programs
After using Tab or the arrow keys to select an item in the Dock, you can press Command-Q to quit it. Even if the program is in the background, it will quit without being brought to the forefront, unless it has unsaved changes, or otherwise requires your attention when quitting.
Adding and Removing Items
Removing items from the Dock using the keyboard will require you use the up arrow to access the item’s contextual menu and select the option to remove the item. However, to add items, you can make use of a hidden menu item in the Finder. Select your desired item, and then add it by pressing Shift-Control-Command-T. You can then use Control-F3 to change focus to the dock, and use the Option and arrow key combinations to move the item to the location of your choosing.
Hiding and Showing the Dock
A final option is to quickly hide and show the Dock, by pressing Option-Command-D. Note that when hidden, you can still access it by pressing Control-F3, or whatever custom hotkey you have assigned.
Thanks for the reminders. I use the Control-Option-Down arrow keys to move focus to the Dock because they are easier to get to than the Tab key or the F8 key. For me the biggest advantage of using the keyboard to access Dock items is that you don’t need to hold down the left mouse button to access the contextual menus, nor hold that button as you mouse through the list(s). The only shortcut that might be more trouble than it’s worth is for adding items. You have to select the item in the Finder anyway; dragging it to the position you want and dropping it there seems to me to be more efficient than using multiple keyboard shortcuts. But that’s just me.
There is an additional use for this option: Helping you control a Mac when the mouse is not working for some reason. That by itself is priceless.
It’s also priceless for visually impaired people, as it plays nicely with VoiceOver.
I have more then two dozen items in my Dock. Using the scroll thru the entire Dock seems stupid.
I keep my doc organized rather placing the apps or folders helterskelter in the dock. For example i know where ( L or R or Middle )of the Dock aliases to the apps or folders are located. Unfortunately the Apple Dock ” system ” is somewhat limited.
Which is why i use LaucnBar whereby i have assigned short cut keys to launch applications, documents, folders and what ever else i want to launch into action except my kids that are near impossible to launch into action.
Aw, this was an exceptionally nice post. Taking the time and actual effort to
generate a superb article… but what can I say… I hesitate a whole lot
and never seem to get nearly anything done.