First, edit the form design, from the main select list, select Form and set the Columns to 2. Set the Column width to be half the form width.
Then from the main select list, select the field set. Set the Left and right padding of the field set to 10px.
in the form contents, there are 2 ways to make an element be on the same line:
1) add a field set with 2 groups in it. for the second group, check the option to "Continue on same line as group above"
1) Add a field set with a group in it. edit the group. Select a line and click the plus button to add a new set so that you have 2 sets on the same line.
