FH Gemming

Hi Guys,

This FH, I plan to remain at +5 as I want to rake the Heavenly Bud as an FH prize so I don't want that included in my would-be rewards in the next FH. I am currently comfortable between Rank 700-800 and I want to know how to gem strategically in the last hours of FH tomorrow as I know keeping up at +5 on these hours is hard because of the heavy gemmers. I just have an ample amount of gems I am willing to spare and please let me know the time in gemming for this. Thanks all!