Currently, the officially supported way of installing CMO requires one to install the add-on via Deployment Center to a CMS site running 7.5.394.2. However, with many clients no longer using Deployment Center to create Episerver sites from scratch - often creating sites via Visual Studio extension - it's often not a viable option.
Here is a workaround:
Installing CMO on website consists in copying binaries and registering CMO module, location and handlers/modules in web.config.
In order to see what should be added in web.config, You can create plain Alloy site, backup web.config file, install CMO using deployment center and compare updated web.config with original file in any merge/comparison tool.
There some information pieces that you can use to install/uninstall CMO manually:
Installing and configuring the aggregation service (written for previous CMO versions, but should be accurate):
Configuring the Statistics Handler (written for CMO 2.0, but in general is accurate. I think browser definitions are not required now.):
Configuring after the Installation (written for CMO 2.0, but most of the steps are accurate):
Uninstalling CMO (written for CMO 2.0, but most of the steps are accurate):
Configuring EPiServer CMO Thumbnail Service on Windows Service 2008 R2 or later versions:
Set of blog posts about basic CMO component and deployment scenarios:
EPiServer CMO components and simple installation scenario - http://dmytroduk.com/techblog/episerver-cmo-components-and-simple-installation-scenario
EPiServer CMO: advanced deployment options - http://dmytroduk.com/techblog/episerver-cmo-advanced-deployment-options
EPiServer CMO in load balancing environment: simple scenario - http://dmytroduk.com/techblog/episerver-cmo-in-load-balancing-environment-simple-scenario
EPiServer CMO in load balancing environment with separate editing server -http://dmytroduk.com/techblog/episerver-cmo-in-load-balancing-environment-with-separate-editing-server
Episever developer links:
https://jstemerdink.wordpress.com/2016/09/18/cmo-and-episerver-9/ (Third-party NuGet package alternative installation)