Is it a product site or a Blog ?
If it is a product site create and link a relevant Blog with your site. If it is Blog ...
Write good quality useful content for your readers.
Organize and Optimize your content for your readers and googlebot.
If you are unable to do the above, recruit or hire people who can do it for you.
One of the ways to make your site interesting for many people is a showing a videos or maybe a tutorial video, and share it for a free to YouTube for example and it’s a great way to get unique visitors to your site,
Don't worry about trying to get more unique visitors right now. If the existing visitors you have all bounce, the better strategy is to work on how to make the most of your existing visitors. Work on lowering your bounce rate, and getting existing users to visit more pages on your site.
Once you've done that, then you can work on gaining additional users, feeling confident you're getting the most out of each one of them.
I have one website but its bounce rate is very high i want to increase unique visitors for my site. So anybody tell me what can i do to get unique visitors for my website.
The sole reason behind high bounce is low quality content, You need to improve it. As far as unique visitors is concern, You need to do proper marketing using SEO,SEM or any other online marketing idea
concentrate on the visitors who are already coming to your website. Look for the keywords you are ranking in the search engines. It may be possible that you are ranking for a keyword which is not appropriate for your website. If you work on the appropriate keywords and get a descent ranking in search engine you will not loose the coming visitors.