What is the test for a defendant to waive his right to self-representation?

The Sixth Amendment "guarantees a [criminal] defendant a right to counsel but also allows him to waive this right and to represent himself without counsel." United States v. Erskine , 355 F.3d 1161, 1167 (9th Cir. 2004) (citing

[923 F.3d 1234]

Faretta v. California , 422 U.S. 806, 820, 95 S.Ct. 2525, 45 L.Ed.2d 562 (1975) ). To successfully invoke the right of self-representation, a defendants waiver of counsel must be "timely, not for the purposes of delay, unequivocal, and knowing and intelligent." Id.