offtopic : change your avatar its sucks.

ontopic :
Code: 
#Main Domain
server {
listen 0.0.0.0:80;
server_name domain.com www.domain.com;
location / {
root /home/domains.com/www;
}
}

#Sub Domain
server {
listen 0.0.0.0:80;
server_name sub.domain.com www.sub.domain.com;
location / {
root /home/sub.domains.com/www;
}
}

#Another Sub Domain
server {
listen 0.0.0.0:80;
server_name sub2.domain.com www.sub2.domain.com;
location / {
root /home/sub2.domains.com/www;
}
}
change 0.0.0.0 to your IP. this is just the main structure of how to create domain and subdomains.