amusewiki clone-site export --directory /tmp/export-sites-$(date -I)

Copy the directory over and on the new instance run

amusewiki clone-site import /tmp/export-sites-$(date -I)/*

Clone the git repositories in /var/lib/amusewiki/repo/

Install the logos in the texmf tree, if you use them, and run:

mkdir -p `kpsewhich -var-value TEXMFHOME`/tex/generic/amusewiki/data
cp mylogo.pdf `kpsewhich -var-value TEXMFHOME`/tex/generic/amusewiki/data
texhash `kpsewhich -var-value TEXMFHOME`
kpsewhich mylogo.pdf

Finally, rebuild all the imported archives (if you have large sites, this will take a while, so execute it under screen or tmux).

amusewiki bootstap-archive

You probably want to adjust the global nginx configuration for the usual suspects, like gzipping javascript and max body size.

If you used to serve the git repositories via git-daemon, install it and export the repo, e.g.

touch /var/lib/amusewiki/repo/amw/.git/git-daemon-export-ok
cd /var/lib/git
ln -s ../amusewiki/repo/amw/.git amw.git