When a visitor visits your web or landing page and takes a desired action (such as buying a product or signing up to a newsletter) that is called a conversion. Improving the likelihood that a visitor will take the desired action (or convert) is called conversion rate optimization and is one of the most important things you can do to improve your marketing efforts because once you lose a visitor they tend to be gone for good.
Conversion rate optimization can involve many tweaks and changes that will lead to desired action. You should make sure your landing page design is pleasing and clearly lists the benefits to the customer. Make sure that the copy on the page is persuasive and contains clear calls-to-action, such as ‘Subscribe Now!’. Make your site design clear with a logical to navigate structure so people can find desired information easily. Analyze and test different approaches to see what works best.