What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
To confirm, are you trying to change the overall width of your form?
If that is the case this can be done within the Form Designer under "Form Layout"
You can increase of decrease the number to change the frame of your form.
I increased the width on a clone version of your form here: http://form.jotformpro.com/form/50467151244955
If you were looking to achieve something else, please provide us with more information and we would be happy to assist you.