The best way to advertise your new casino is to put in a lot of work I'm into promotion in form of promos and giveaways, or if you want to make more noise on the forum you can do a signature campaign also.
•Signature campaign
•Social Media exposure
•Promotions and giveaways
•Art competition
•Blog/Video/Review campaign
As long your budget permits you then the more the better because
we know that marketing does plays a big role on every business.