It's often pretty hard to start up a new roleplay since there are already so many and new ones tend to get lost in the shuffle, but there are a couple of things you can do to help yours catch people's interest. I'd really recommend emgeal's guide
How to Start a Roleplay for pointers on how to set up an RP that will interest people and make them want to join, since that's one of the biggest factors in whether an RP succeeds or not. An interesting title with a very brief description of what the RP is about can help (e.g. "The Sound of Drums (Civil War RP)", "A Feline's Fancy (Anthro Cat RP)"), since the description will tell people who are just skimming the board if your RP is something they might be interested in while the actual title helps it stand out and might intrigue people so they click to find out about it. Once they're into your RP thread, emgeal's guide explains very well how to best keep their interest, so I'll direct you over there for that. As for advertising your RP, the only place to do that is in your signature; you can make a text link with the title of your RP, or if you're feeling creative maybe make a banner or stamp for it that links to the RP. Other forms of advertising aren't allowed, so you can't send PMs to people (unless they're close friends who you really think would be interested in the RP) or randomly post links to it or ask people to join it in unrelated threads. Good luck with your RP! ^^