how i can generate sale on click bank

Your first step should be keyword research. you need to find what people are looking for, and then give it to them.

Sorry do you mean you're going to be an affiliate promoting other people's products or you're going to be promoting your own product through clickbank?

Assuming you're an affiliate, I'd recommend:
1. Keyword research (long tail keyword with at least 1,000 monthly views and low competition)
2. Set up a WP blog with an exact match domain name, if possible
3. Fill the blog with QUALITY original content, related to your niche with links to authority websites throughout content.
4. Send QUALITY backlinks to your website
5. Send QUALITY backlinks to your backlinks (some will say this is unnecessary but I stand by it)
6. Continue with other safe SEO practices until you can rank your blog on page #1 of Google for your keyword or you start getting consistent traffic.
7. Set up a "money post" with a link to the clickbank product you are trying to promote.

Hope this helps. Obviously there's a lot more to it than that, but that would be the general idea of what I do on a daily basis. Another option is list building, which other warriors could tell you more about.

You need traffic to make sales with ClickBank. You can use social media such as Facebook, Linkedin and Twitter.