Hello diegodlv,
yes I agree to you. But this same document provides the details of how to create a vmdk disk in vmfs partition and then share it between multiple nodes using multi-write method. it has screen shots as well. this is one of the best documents where it shows the steps in proper configuration mode. So I would suggest take these steps (preparing the nodes specially on page 16 and then between 23 to 26).
Once you get the shared disks ready (which is your primary aim) then you can have OCFS2 or any clustering file system in those disks and share it between the nodes.
or do you want to know the OCFS2 creation steps? Cause this document covers the step before that and since I have worked more on RAC and ASM so I had created ASM on those shared disks.
But how to create OCFS2 steps you would get in many oracle blogs site.
This document would provide details steps before that..
https://www.vmware.com/files/pdf/partners/oracle/vmware-oracle-rac-deploy-guide.pdf
Hope this helps.