Multisite doesnt work and gives 404 error..what mistake am i making?

Hi,
I am not sure where i am doing mistake i have read many many times all the articles related to multisite but still i couldnt upload my new site on new subdomain.

I have WHM (Cpanel) and i have created a domain like example.mydomain.com , then i have used putty and went directly to the root directory.

my root directory is something like this

suppose if i have made a new subdomain call example then its username is examp123 and that same username comes as a folder inside my root directory.
for e.g.

/home/examp123/public_html/

while my real parent site is inside /home/mymainuser/public_html <-this one workds when i use www.mydomain.com

so these are both users to connect
1)examp123
2)mymainuser

after that i have deleted examp123 since i have read on many places that i must delete the subdomain folder and create a symbolic link. So by using putty i have successfulyy deleted whole folder of examp123 and instead of that i created a symbolic link as follow

ln -s "/home/mymainuser/www/" "/home/mymainuser/www/example.mydomain.com"

i tried this but didnt work
then i tried many variation including "/home/mymainuser/www/example" ,"/example" or "/example.mydomain.com" and many others but all the time when i run example.mydomain.com it shows me 404 error. In first i thought maybe i shoudlnt delete that user folder so i have created another user like motorsr , with new subdomain as motors.mydomain.com

this time i didnt deleted the folder from the root and instead of that i tried to create symbolic link , it still didnt show me the current drupal site which i have inside my "All" folder of sites.

i have already put settings and created sub folders inside sites e..g like sites/example.mydomain.com , sites/motors.mydomain.com etc... but i am not sure what mistake i am doing and why i am getting 404 error for example.mydomain.com while motors.mydomain.com works but it always shows folder information rather then redirecting the drupal queries.

Please help me guys to solve this issue.