Read the News
The Arch Linux News is posted here:  You can subscribe to the rss feed by adding:  to your favorite feed reading software. You can also get news by subscribing to the Arch Announce mailing list: .
Pay special attention to news items with "manual intervention required" in their header. You can avoid a lot of trouble and embarrassment by reading the instructions in these news announcements and following them.
- When you update, check pacman output for instructions related to updated packages.
pacman -Qdtto find orphaned packages, and
pacman -Qo <file>to find out which packages that own individual files.
- Search for .pac* files and merge them with configuration files (see Pacnew and Pacsave Files).
- Check for out-of-date or unmaintained AUR packages on your system. Sometimes these can cause problems when you update.
- Check the size of
/varand clear pacman's cache once in a while. A useful tool to assist in this process is AUR.
- Check disk (use fstab options to check at boot)
- Search logs for errors (list scripts, tools to make this easier/more automated)
- Look into errors as soon as possible - do not leave them unattended to.
- Linking random libraries together to get a program to work.
- Updating once a year.
- Copy-pasting commands into the terminal without at least reading man pages to understand what you are doing to your system.