By selecting the hosted form option, you can design a sign up form to be hosted on a particular link which you will be provided. You can customise the colour, the title, the label on the button, and the message they receive once completing the form. You also have the choice to collect names if you wish to collect this data. There is also the option to redirect them to a separate link upon completing this sign up instead of displaying a message. All the changes you make are displayed on the preview on the right.
Once you have saved the changes to your form, you will then be provided with a URL to a page where this hosted form can be found. You can add and share this link where you like, and people that click on the link will land on this sign up form, from which they can sign up to your list.