You don't really. You probably could theoretically, but really any competition that goes after a smaller subset of those words is going to blow you out the water.
I prefer not optimising for more than 2, 4 at a push. I certainly wouldn't go for more than 8 very closely tied phrases/words.
Why dont you add 16 pages to your website each targeting one keyword. Also do this in a silo structure. Did this to my main site and it works good. This way your main page can rank for a few keywords then the rest of them can rank with the help of deep linking. This juice is then passed to the main keword/homepage.
What is the reason you want to rank just one page?