To design the counter you can change the font size colour text ETC of the number by click8ing like a standard element.
To set the number of the counter click it and then press settings. The below are explanations of what they do.
Start from - Where the number starts
Ending Number - Where the number ends
Duration - How fast it operates the higher the number the slower it runs
Prefix - Text at start of number IE. $
Suffix - Text after number IE %
Start on Viewport enter - Will start the counter when the counter enters the view point
Comma Separator - adds a comma to the number
Increment - Increases number by the increment entered
Reset on click - Starts the counter again when clicked