Help yourself to some peaches.
Can the subject be yourself?
No.
The subject is an implied "you" -- (you) help yourself
yourself is the direct object
yourself is a reflexive pronoun, so it requires an antecedent; in this case, the invisible "you"
Can the subject be yourself?
The subject is an implied "you" -- (you) help yourself
yourself is the direct object
yourself is a reflexive pronoun, so it requires an antecedent; in this case, the invisible "you"