Ask how. Examine the phrase "He speaks slowly." The word "slowly" answers the question of how he speaks. Usually, adverbs that tell how end in -ly.
Determine if it is good or well. Well answers how something is done and is an adverb while good describes how something is done and is an adjective. "You did a good job" describes the job you have done. "You did the job well" answers how you did the job.
Identify the verb from the adverb. Verbs are action words that tell what the subject of the sentence is doing or has done. The sentence "Birds fly quickly" contains both a verb and an adverb. The subject of the sentence is birds. The action word is fly, this verb tells what the birds are doing. The adverb in this sentence is quickly, it describes how the birds are flying. You cannot have a subject and an adverb without a verb. The sentence "Birds quickly" is not a complete sentence because it does not tell you what the birds do quickly.
Determine the type of adverb in a sentence. Adverbs of time tell when something happens while adverbs of frequency tell how often something happens. For example, in the sentence "Do it soon," soon is the adverb of time, it tells you when to do it. The sentence "He usually goes hiking" contains an adverb of frequency. Usually tells you how often he goes hiking.