Understand the importance of a full dress rehearsal (FDR) before the final cutover. We will outline planning, execution, and lessons learned.

FDR target
As a Full Dress Rehearsal might be new to other project participants FDR targets and procedure need to be well aligned and shared. 
In general with an FullDressRehearsal Cutover tasks, Communication, Meetings, and toolset should be simulated as close as possible to the final Cutover setup. 
The FDR needs to be executed after close out of testing cycles to ensure stable FDR environment. 
The final cutover setup need to updated based on the FDR learnings.

FDR planning
As for the final cutover all plannings must be setup dedicated for the Full Dress Rehearsal
o FDR scope: participating affiliates & system landscape
o FDR KeyDates
o FDR Meetings & communication to central Team & to all Project leaders
o FDR Mission Control centre
o FDR Ticket handling
o FDR Food & Beverages

FDR staffing
As activities for FullDressRehearsal are time critical and should reflect real cutover situation as much as possible also a detailed staffing plan needs to be setup for project management, IT & Business roles:
o Who needs to be available when?
o For critical activities shift and backup planning needs to be considered
o Remote / onsite policy needs to be defined

FDR execution
execute FDR
o System setup
o simulation Ramp down
o Data migration & approval
o Final system setup & initial postings
o FDR ramp up simulation 
o FDR Quality Gates
o FDR Ticket handling

FDR lessons learned
Execute FDR lessons learned sessions with all stakeholders and update final cutover procedures for Business & IT, Central & local participants as well as stakeholders. Have a look on
o Tasks / Sequence / timings
o Communication / Cutover monitoring & reporting
o Risk management approach
o Toolset

Cutover readiness / Cutover Quality Gate 1
Based on implemented FDR lessons learned the final cutover readiness should be evaluated = Cutover Quality Gate 1.
Is everything prepared to start final Cutover ?
An detailed approach can be found here: https://community.sap.com/t5/enterprise-resource-planning-blogs-by-sap/sap-project-cutover-readiness-assessment/ba-p/13516762