Hi there, while installing Gentoo for my Pi I noticed how there's a lot of confusion, and many (good) alternatives around how exactly you should proceed with the installation.
I compiled a shortish guide of the most popular ways of installing Gentoo on the RPi (including links to tutorials by me or by others), and wrote up some pros and cons of each Gentoo installation method. I'd be happy to hear your feedback, and perhaps you can point it out if I have missed something or some newer installation method pops up (maybe an automated qemu script? ^^).
Anyway, long story short: here is the overview article.