It's important to be specific. Record as much information as possible about the bird when you first see it. You may only have a quick glance. Sometimes it is easier to remember short answers. The best thing to do is write it down.
Serious birders keep a journal of birds they've seen.
You could start your own bird journal. Here are some questions to ask yourself when identifying a bird. Print out the list to keep with you. Focus on each part of the bird separately. Look at shape, size and color.