What is the meaning of Yourself?

Your own self (singular).

You (singular); used emphatically, especially to indicate exclusiveness of the referent's participation in the predicate, i.e., that no one else is involved.

You (singular); when "you" is not mentioned previously, a hypercorrection sometimes perceived as being more polite in formal and professional conversation.

Emphatic plural 2nd person pron.

Source: wiktionary.org