I need to blog this for my future reference.. (I have encounter this problem many times before and this is the first time I succeed.. ahaha)
1. Open Tomcat properties:
2. Check the Catalina base folder
4. Add role and users as follows
5. You can now login to tomcat manager using the username and password as in configuration above.
And now I can peacefully continue working on my pdf printing applet... yeahooo!