There are only two ways to take care of the check. Either one person pays, or n people pay equally like the opening scene in American Psycho. Any sort of bookkeeping at the dinner table is really bad manners.
EDIT, more etiquette hints:
when looking at the check, make at most a quick glance. Ideally don't look at the check at all. If you can't trust them to prepare a check you probably shouldn't trust their cooking either.
How do you figure out who picks up the check?
- if you are dining with the boss, you're the one who pays
- if you're dining with customers, you're the one who pays
- if you're dining with your girlfriend and her female friends, you're the one who pays
- if you're the host in any sense, you're the one who pays
- if you're dining with students and you're the only one who has a job, you're the one who pays
- if you're the one who went deep on the wine list, you're the one who pays
There aren't many times that a check gets split, or any sort of turn-taking applies. For the most part, you're the one who pays.