Many beginners think that the best way to use a field is while you’re in the field. The problem is that while you are looking at the field guide in the outdoors, you are NOT looking at the bird. The field guide is best used before and after going into the field. Before you go out look through the guide at the birds that you are likely to see. In the field observe and take notes. You can always identify it later. The more observations you make, the more likely you will be to identify it later. Observe size, bill, markings, behavior, and habitat. If possible, write them down while you are in the field. Then when home, look through the field guide, comparing your notes to possibilities. Don’t worry; no one identifies every bird.
Look through your field guide as much as possible; time spent here will significantly improve identification in the field. At the risk of sounding a little too candid, a great place to leave a field guide is by the toilet.
Which field guide should I use? There is no best field guide. Each has its best points, and the best option is to use several of them. Several of them are listed below with links to additional information.