[0utLaW_]

Use a gamemode that are rare, and unique but people like play in.
If you just use RolePlay, it has to be very very unique, still you chanece to get player are very slim because many rp out there who have many weird yet unquie features.
Mix up the suggeston above and you can start

Get a stable hosted server
Put it on hosted list
Get domain, not www.roleplay.gaysite.com but a standard one
Advertise it on sa-mp and *******
Have your server in more than one language
If you can do russian server, i bet you will get more playert than you expected)