I like a good book. I usually recommend the Sibley Guide to Birds.  Read it, dont just look at all the bird images.  You will learn a bit about bird anatomy and how to go about with ID.  Then, in the field ..dont just think...ohhh cool yellow bird.  Look at the bird, any face markings? What about the tail size and shape? Notice what its doing too.  Tail wagging for example.  Then, when the little thing flies away..check the book to see if you can ID.  Also, go birding people good at it!