EHS, where to start?

Hello Everyone! I am very new to EH&S and specially to the Occupational Health submodule...

Can anyone tell me where to start customizing? I undesrstand that before going into OH I need to customize the Basic Data and Tools... so, is there any extra documentation besides the SAP Help? Can I leave the Basic Data and Tools in SAP standard? What should I check?

Thanks in advance!!!!