I want to make a little customization of the Share tier.
For this purpose I have prepared the relevant AMP file in which override some current properties. I know how to do it in another way, but I interested in that way.
Should I make any backups before deploying AMP?
Backups of what? Your WAR file will be backed up, unless you specify a -nobackup command.
http://docs.alfresco.com/5.0/tasks/dev-extensions-tutorials-simple-module-install-amp.html