Disclaimer:
The information in this site is the result of my researches in the Internet and of my experiences. This information below is solely used for my purpose and may not be suitable for others.

1. # eix-sync
   This is same as below:
   root #emerge --sync
   root #cp -a /var/cache/eix/portage.eix /var/cache/eix/previous.eix
   root #eix-update
   root #eix-diff
2. # glsa-check --list
   1. # glsa-check -t all
      When above command returns [N], execute this.
   2. # glsa-check -p $(glsa-check -t all)
      To see what packages would be emerged.
   3. # glsa-check -f $(glsa-check -t all)
      To apply the fix.
3. # eselect news read
4. # emerge -uUDavp --with-bdeps=y @world
   -u (--update): Updates pkgs to the best version available
   -U (--changed-use): Include installed pkgs where USE flags have changed since installation.
   -D (--deep): Forces emerge to consider the entire dependency tree of pkgs
   -a (--ask): Display what will take place
   -v (--verbose): Run in verbose mode:
   -p (--pretend): Display what *would* have been installed if -p weren't used
   --with-bdeps=y: Pull in build time dependencies that are not strictly required
   If no problems flagged in above, go to xxx
   Otherwise, fix any problem(s) flagged by the emerge --pretend, then go to #4 again.
5. # emerge -uUDav --with-bdeps=y @world
   If any issue(s), fix them and go to #5 again.
6. # emerge @preserved-rebuild
   Run this only if specified in output from above.
   @preserved-rebuild: Update pkgs that still use old libraries with new ones
7. # emerge --ask --depclean
   Run this only if specified in output from above.
   --depclean: Cleans the system by removing pkgs that are not associated w/explicitly merged pkgs
8. # dispatch-conf
   Tool that aids in merging the ._cfg0000_[name] files
9. # eclean-dist --deep
   Clean the source files directory, /var/cache/distfiles
10. # eix-test-obsolete
    Search for obsolete packages on the system
11. Wait for at least 24 hours to a week or so, then go from beginning.

That's all!
-gibb