This is a guidelines you have to do while building your list:

Set up a good web form in your site that immediately follows the end of your content. Although some may say this is too soon to subscribe for a website visitors application, try to remember that your own homepage should give a quick good impression. If for some reason a website customer finds something that he or she does not like and turns them off, they may simply ignore joining.You also must choose excellent autoresponder services exactly like aweber, but If you can not afford with aweber then you can try aweber alternative

A good web form for opting-in to an opt-in list is not hard to do. Just write an easy short statement about exactly how they want to see more and get updated regarding the site. Then there should be an area where they might place in their names as well as e-mail address. This web form can automatically save and send you the data’s inputted. As more people sign in, your list will be growing