Sugarlogic - Set date when checkbox = true ??

Hi, 

I'm quite new to SugarLogic, so I need some guidance! 

I have a checkbox-field and a date & time-field. When the checkbox is set to true, I want to set the date & time (when the checkbox is set) in the date&time-field. 

I'm guessing i need to use the ifElse-statement, together with equal() and now(), but I'm doing something wrong with the syntax. 

Would really appreciate some help!