From AlliedModders Wiki
Create a git branch.
Update master.cfg in buildbot buildmaster. Don't forget to push the change to github.
mount -orw /mnt/downloads on web01.
mkdir /mnt/downloads/smdrop/<new release folder>, chmod 775 it, fix ownership.
mount -oro /mnt/downloads.
Fix sm_commit_log by updating last ~N master builds to be the new stable branch.
Update ~sourcemod downloads.php.
Update ~sourcemod vbcompiler.php.
Update forums newpost.php and editpost.php (search for ccversion). Do this on staging, create a production PR in bitbucket, then pull.
Create a compiler-1.<version> folder, drop spcomp + includes there.
Add an entry to web-commit-updater/updater.php for the new version.
Force builds on the new dev and stable branches via pushbuild.txt.
Add a script for the new version in ~sourcemod/update.
Change the ~sourcemod/compiler symlink to the new version.