Creating a form that will auto forward! Urgently needed help!

Hi everyone out there. Currently i am working on this form that required 3 person to verified. The thing is after the first person who verified it will auto forward to the second person to verified and after the second person verified it will forward to third person and lastly return back to the first person. The 1st person field is pRequestor, 2nd person is pSectionHead and the 3rd person is pHeadLogistic. There will be a send button for each individual to forward to the next person. I got no ideal where and how should i start the code. Anyone can help!! Thanks a million.