17Hats has a great video walkthrough on how to create the lead contact form here:
After you have created your contact form, locate the green Install Form button and choose the "Insert Form on Website" option.
This will pull up a pop-up window with an embed code you will want to copy into your clipboard.
Next, Log into Showit and add the Embed Code widget to the canvas you want your contact form added to. You will then paste the copied code from 17Hats into the Embed Code field in the right toolbar.
Lastly you will want to resize the embed box in both desktop and mobile views to ensure the full form is displayed.
Then be sure to preview your new form and test to confirm you are receiving messages in 17Hats.