I have been meaning to write up a blog post about how to use code completion in XCode for a while now.  Luckily for me, John at Mac Developer Tips beat me to it:

http://macdevelopertips.com/xcode/xcode-code-completion.html

Essentially, this article shows you how to have XCode act like your significant other and finish your sentences for you.  For example, if I start typing in the letters “NSL” and press the escape button it may suggest “NSLog(..” and if I hit the tab button it will finish writing out the statement for me.

The article tells you know to configure this and shows you an example or two.  I highly recommend using this feature.  Here is the article again:

http://macdevelopertips.com/xcode/xcode-code-completion.html

What is your favorite XCode trick that you have come across so far?