Reflexive pronouns are formed by the addition of the suffix self (singular) or selves (plural) to simple pronouns such as my, your, her, him, it, them and our.

My + self = Myself
Your + self = Yourself
Our + self = Ourselves
Them + selves = Themselves
It + self = Itself

When the subject and the object refer to the same person, a reflexive pronoun is used for the object.

I cut myself. (Here the subject and the object refer to the same person – I.)
You cut yourself. (Here the subject and the object refer to the same person – you.)
She cut herself. (Here the subject and the object refer to the same person – she.)
The child cut itself.
We cut ourselves.

Note: When self is used independently, it is a noun and not a pronoun.
An honest man keeps his self free from all vices.
One’s self is always more important to one than anything else.

Emphatic pronouns
When reflexive pronouns are used to put emphasis on a particular noun they are called emphatic pronouns.

He himself told me this.
I finished the job myself.
They themselves admitted their mistake.
We ourselves witnessed the accident.

 
Notes:
The emphatic pronouns cannot be used as subjects. It is therefore wrong to say:
John and myself went there.
Herself swam in the river.
I invited herself to tea.

The correct sentences are as follows:
John and I went there.
She swam in the river.
I invited her to tea.

Difference between reflective and emphatic pronouns
A pronoun is a reflexive one if the action of the subject reflects upon the doer. Emphatic pronouns, on the other hand, are used to just emphasize the action of the subject.

He cut himself. (Reflexive: here the subject and object refer to the same person.)
He himself cut the cake. (Emphatic: here the emphatic pronoun himself merely puts emphasis on the noun he.)
I spoke to the principal myself. (Emphatic)
You must blame yourself for the loss. (Reflexive)

Note that an emphatic pronoun can be removed from the sentence and the core meaning would not be affected. A reflexive pronoun, on the other hand, is indispensable. The sentence wouldn’t make complete sense if you remove the reflexive pronoun.

Compare:
He himself cut the cake. He cut the cake.
He cut himself. He cut …what?

You will have noticed that in the first pair of sentences, the core meaning doesn’t change when the emphatic pronoun himself is removed from the sentence. In the second pair of sentences, the meaning changes or becomes incomplete when the reflexive pronoun is removed.

Notes:
If the reflexive pronoun in a sentence is replaced by the reciprocal pronoun ‘each other’, the meaning of the sentence changes drastically.

Compare:
John and Peter blamed themselves for the loss. (John blamed himself and Peter blamed himself.)
John and Peter blamed each other for the loss. (John blamed Peter and Peter blamed John.)