Here's how:
Adjective: It describes a noun.
* Example: "This is the easier path." (Describes the noun "path")
Adverb: It modifies a verb, adjective, or another adverb.
* Example: "He did the task easier this time." (Modifies the verb "did")
It's important to understand the context of the sentence to determine whether "easier" is functioning as an adjective or an adverb.