How do can I determine the exact position "coordinates" I need to use?

You can bring a paper and draw a rectangle (8 cm width,6 cm height) , 1cm=100 pixel. then divide it with roller , every 1 cm draw a line, in the end you will have a grid , every connect point have a value. That's the same thing with those values in Screen. http://1.bp.blogspot.com/_TDPzTFmd880/TVB5MtBIAHI/AAAAAAAAApM/wsA3HUzULtU/s400/grid.PNG Ask me if you have another question, i am new also but it is better to work together

I have this idea in my head to create a javascript code that will put a grid on the page and the cursor can tell you the exact position of the coordinate. But that is way ahead of my current skills. lol. I'm sure someone already created the code, just have to google it.

You must first be able to get the element itself, which is this using javascript own

var elem = document.getElementsByTagName("em")[0];

or

var elem = document.getElementsById("em")[0];

or any other selector.

Then, having the element, you can call

var result = elem.getBoundingClientRect();

Which you'll then be able to access all 4 dimension of the elements coordinates

console.log(result.top, result.right, result.bottom, result.left)