What a wonderful pillow! Have you done it by ________ ?
you
your
yours
yourself
Yourself’ (singular form) and ‘yourselves’ (plural form) are reflexive pronouns, being the reflexive forms of ‘you’. Reflexive pronouns end in -self or –selves: myself, yourself, herself, himself, itself,ourselves, themselves They refer back to the subject forms of personal pronouns. We often use reflexive pronouns with the preposition ‘by’ to mean ‘alone’ or ‘without any help’: Why don’t you go by yourself?; The children made the entire meal by themselves.; He lived by himself in an enormous house.; She walked home by herself.; The children got dressed by themselves.; I prepared the whole meal by myself.‘Oneself’ is the reflexive form of the pronoun 'one' when it refers to people in general or to the person speaking, it is also used in this phrase ‘(all) by oneself’