Overview
You can backup your account files and you should do that at least once after you created the account. This ensures that you still have your private key to access your account if anything goes wrong.
Complete Backup
To backup everything including your account data simply use the backup functionality. All created backup files are stored in folder backups/. This is considered the most comfortable method. If required you can restore the backup via the GUI. Later you sync again with friends and everything is fine.
User Backup
However you can also manually extract your account data using the get_user.sh script that is part of the toolset. A user profile consists of the following files and folders:
keys/ADDRESS
control/keys/ADDRESS
control/keys/ADDRESS.sct
userdata/ADDRESS/
proofs/ADDRESS/
trx/ADDRESS.*
If you want to extract only your profile first unpack get_user.sh from the tools.tar archive:
tar -xvf tools.tar get_user.sh
Now run the script and handover the address of the user you want to extract:
./get_user.sh ADDRESS
Import
If you want to import your profile you will need to run import_users.sh of the tools.
First extract the archive containing the profile data in the wallet home directory:
tar -xvf YOUR_PROFILE.tar
Now unpack the import_users.sh script from tools.tar archive:
tar -xvf tools.tar import_users.sh
Then simply run it without any parameters:
./import_users.sh
The script will check for new public and private keys and will import them to the GPG keyring.