Hello Luis,
As Amy mentioned, refer PM Handbook which is an excellent source of information giving details of how your project management experience should be spread out across all five process groups. Create an Excel sheet to log your major projects with total duration of each project ( start date to finish date ), total number of hours ( considering 8 hours a day ), how many hours dedicated for the project ( if you are doing multiple projects simultaneously, you don't dedicate 100% of your 8 hours on one project ) and then allocate % of your total dedicated time for each process groups ( IN, PL, EXE, M&C and CL ). Total % added up should be 100%. Just remember, don't calculate overlapping time period for multiple projects in your worksheet. Same excel sheet should capture the name of the organization, supervisors name, contact phone and e-mail address so that if audited by PMI, you can remember who to contact for obtaining clarification. Fortunately, I did not get audited by PMI, if called for an audit, this excel sheet would have been a great tool to me.
Hope it helps.
B.Eng. PG in Supply Chain Management, PMP, Green Belt, SAP certified