My top tip would be - remember to take your notebook and sketch what you see, particularly the obvious colours and markings. This makes it easier to compare to images/illustrations in your bird book as so often by the time you have your book open the bird has disappeared - at least this way you are left with some notes.
Have a look also at these pages on the RSPB website: http://www.rspb.org.uk/advice/watchingbirds/
And these tips from an American site should be useful too: http://www.birding.com/beginning_birding.asp
Good luck and let us know how you got on.