Keep this hack in mind for your forms and sign-up sheets. Make opting in the default choice and leave opting out as a secondary choice that people have to choose by hand. An example is when people are purchasing a product from you make the newsletter sign-up checkbox ticked off by default. This is great because most people choose the default choice without thinking and this way, whether they intended for it or not they will be reminded of the greatness of your product in the future. This guide will further explain this hack.