VER SP 1.2 is “Establish and maintain the environment to support verification.” Companion practices are OPD SP 1.6 “Establish and maintain work environment standards.” And IPM SP 1.3 “Establish and maintain the project’s work environment based on the organization’s work environment standards.”
So what this all means is that you have to define at the organization level what the standards are for verification environments, in IPM define the project’s verification environment(s) in the project plan, and in VER define what the various verification environments are. When you consider VER, there are at least two and possibly more verification environments depending on the system you are developing. At a minimum you have a peer review environment and a product testing environment. Both of these environments have requirements, resources, equipment, and tools which you will have to define yourself. In the case of peer reviews and inspections the environment is many times just the conference room with a whiteboard, LAN connection, computer, and a projector, plus other requirements. The testing environment may be a specific room and equipment set aside as a testing lab, etc. So, to implement VER SP 1.2 you have to define the requirements for each verification environment that you have defined for the project, along with the resources, equipment, and tools, and then the acquisition of these items to actually construct and maintain the environment(s), which also include upgrades over time.
And keep in mind the CMMI definition of the phrase “establish and maintain”, which means formulate, document, and use. Therefore you need to design the environment, document the environment, and use the environment for verification.