hi lekax,
wen ever we write any proposal , our main motto is to know why we need to write the proposal & to convince the concerned person crux of the subject. so as per my knowledge , in ur proposal of manpower planning u should first mention what is it exactly.. why organisation need it & whats the benefit of manpower planning to organisation. how it will smoothen ur work process in a more professional way & later on u may write down the process of Manpower planning.