Contact Form Multiple Checkboxes in a Column

I’d like to add this to my contact form: http://www.crestedbuttecomputers.com/dev/gravitygroms/gravity-grom-online-registration-from/
<input name=”June21″ type=”checkbox” value=”Sat” />Sat.
<input name=”June21″ type=”checkbox” value=”Sun” />Sun.
<input name=”June21″ type=”checkbox” value=”Mon” />Mon.
<input name=”June21″ type=”checkbox” value=”Tues” />Tues.
<input name=”June21″ type=”checkbox” value=”Weds” />Weds.
<input name=”June21″ type=”checkbox” value=”Thurs” />Thurs.
<input name=”June21″ type=”checkbox” value=”Fri” />Fri.
However – it shows all of the checkboxes next to eachother – followed by all of the names.

Is there a way to get this to show up right?
I’m trying to mimic this registration form where it goes into the days of the week that the camper will attend:
http://www.crestedbuttecomputers.com/dev/gravitygroms/wp-content/uploads/2014/06/Gravity-Groms-2014-Day-Camp-Registration-Form.pdf

Thanks