Update README.md

Author: 0xZDH

README.md

@@ -27,6 +27,9 @@ Install one-liner: `source <(curl -s https://raw.githubusercontent.com/0xZDH/cmd
 If required, the user can modify the size of the maintained history file by setting CMDWSIZE as an environment variable (Default: 3,000):
 * `export CMDWSIZE=1000`
 
+For uses that require larger history files, it is best to include and set the CMDWSIZE variable in the terminals rc file prior to the sourcing of the cmdw tool. For example, add the following to your rc file above the cmdw source line to allow the history file length to grow up to 1,000,000 lines:
+* `export CMDWSIZE=1000000`
+
 ## Command Referencing:
 1. List the executed commands in .cmdw_history with line numbers via:
     * `cat -n .cmdw_history | grep '#'`