In the opening Form Tag you would put the following parameters:-
<form action="mailto:insert the email address here" method="post" enctype="multipart/form-data" name="insert a name here" id="insert an ID here">
Be careful. This is not a very secure way of sending data. If you are collecting data from potential customers then you have a legal responsibility to protect that data. It is OK to collect data like names or email addresses this way but it is not OK to collect sensitive data.