Hope you are well.
Our main documentation starts here:
And cumulative updates here:
The server file is the one that will upgrade the CRM version on the servers and update the DB schema of each org with the new changes. Tools are just secondary as they are not strictly required for the CRM normal operation. Just in case you use those features. SSRS sure it can be considered a required tool as its needed to run reports.
Going into details these are the general recommendations:
– Backup everything
– restore databases on a separate environment to test the upgrade in case of failure.
– You can either do an in-place upgrade where the org is deployed while you upgrade, or you upgrade first the server and then import the org, which will then trigger the update of the Database.
– If in-place, disable the org and apply the patch you desire on all the servers in case it’s a multi server deployment. Then enable the org and apply the DB patch.
– Regarding the tools like email router and SSRS these are less critical in terms of something going wrong during patching. Try to match email router and SSRS versions to the server version you just installed and that’s it. Start with servers and then tools.
This is general ideas, but please let us know what are your specific concerns.
The upgrade steps are straightforward, where the major problems resides while upgrading the database schema due to data inconsistencies due to unsupported customizations and similar.