Selling the click means getting someone from the search engine results pages (SERPS) to click on your site instead of any of the others.
You can quickly test this for yourself. Go search nearly any term and read the titles and descriptions showing in the results. Some yell click me and some make you wonder Huh? Try a couple of them to get ides on what might work better for your site.
In most, but not all, cases the Meta description you have on your site is what will be shown in the SERPS. It is the 2 lines right below the Title, which is the same as your page title at your site.
The maximum number of characters shown is 160 and if you use any more than that you will see your description cut short and ended with …
You want to be descriptive and encourage the searcher to come to your site. Sell the click to him.
