Hello yifan and welcome aboard :wavey:
Most of us get traffic via the following merthods:
SEO – Search Engine Optimization. Optimize your sites for the bigger search engines, exchange links with quality sites in the gambling category and then submit your sites to the larger directories and engines. This is a science that takes a good deal of effort, but its probably the best producer over the long term. Learn as much as you can and apply those techniques and experiment to you find what works best for your site(s).
PPC Engines – Pay Per Click search engines like Overture, Findwhat, 7search and espotting are popular to establish quick traffic to your site(s). Just be careful about how much you bid and select keywords carefully. Note: Many of the PPC engines online are rife with fraud so choose engines carefully.
Offline Advertising – This is another broad avenue to try. Many people use business cards, signs, flyers, newspaper and magazine ads, hand out or direct mail cds, etc….
Hope this helps and good luck!