Closing out an ISDA
See: Section 6 of the ISDA Master Agreement.
On what Event of Default or Termination Event are you relying? With a fair wind it will be Failure to Pay or Deliver. Assuming so:
2002 ISDA
JC’s has updated the step-by-step guide to closing out an ISDA and it is now premium content. You can access it here.
1992 ISDA
Much the same, but with different hyperlinks: JC’s has updated the step-by-step guide to closing out an ISDA and it is now premium content. You can access it here.