Firstly, you need to evaluate the effect your organisation has on the environment. You then need to prioritise ways in which you might reduce them. Next, identify the boundaries of your management system and document your procedures for implementing the requirements of ISO 14001. You will need to ensure these procedures are implemented and then audited. If you have ISO 9000 systems in place, many of the requirements of ISO 14001will already be covered, or can be easily incorporated into them.
Once developed, internal audits are needed to ensure the system carries on working. The setting of targets for the environmental policy and continual measuring against it ensures the system is maintained.