For DF0: the device number must be set to DS0 on the drive and this must have the cable with the twist in it.. I beleive you peel out 4,5,6 and turn them around and put them back in.

For DF1: the drive number must be set to DS1 on the drive and this must have the section of cable that is not twisted.

If you have a DF1: in the machine you need to set these jumpers:

• Amiga 2000 J301 must be on.
• Amiga 3000D J351 must be shorted between 1-2.
• Amiga 3000T J351 must be shorted between 1-2.
• Amiga 4000:

  DF1: ENABLE (J351)	enable 2nd internal floppy (880 KB) as DF1:	closed
  DF1: ENABLE (J351)	no 2nd internal floppy, or 1.76MB floppy as DF1:	open