By configuring ~/.bashrc as desired, each time the user logs into their bash shell the configured settings (of .bashrc) will automatically be set. Now I must be missing something but despite thorough DuckDuckGo'ing I cannot figure out the equivalent for C-shell.
As a reference for bash-shell, there is a thorough explanation of configuring its default settings at the question: What is the .bashrc file?
For reference, I am using CentOS: (As you may have guessed, LINUX isn't my forte)
[user@computer ~]$ uname -r
2.6.32-504.12.2.el6.x86_64
[user@computer ~]$ lsb_release -a
LSB Version: :base-4.0-amd64:base-4.0-noarch:core-4.0-amd64:core-4.0-noarch:graphics-4.0-amd64:graphics-4.0-noarch:printing-4.0-amd64:printing-4.0-noarch
Distributor ID: CentOS
Description: CentOS release 6.6 (Final)
Release: 6.6
Codename: Final
Many thanks for reading this.
-- Edit -- Fixed tags.
-- Edit 2 -- Meant to include that this is also a very good (related) question: What is the .bashrc file?