I am facing problem by using windows 10 in my lumia 535 phone.How can i go back into windows 8.1 again?

I am facing problem by using windows 10 in my lumia 535 phone. How can i go back into windows 8.1 again?

Read more: I am facing problem by using windows 10 in my lumia 535 phone.How can i go back into windows 8.1 again?