In the earliest mention of Shakespeare's "Twelfth Night"; John Manningham's Diary:
A good practice in it [was] to make the Steward believe his Lady . . . in love with him, by counterfeiting a letter as from his Lady in general terms, telling him what she liked best in him, and prescribing his gesture in smiling, his apparel, &c., and then when he came to practice making him belive they took him to be mad.
What is meant by "came to practice" here?