if you think its your radiator leaking,i would fill with water, check all hoses, radiator & thearmostat seal for leaks, you might need to start engine and allow it to come to temperture and preasure before you can see where leak is.when you have found leak and fixed it you will need to empty water out and fill up with proper coolant.
if its your screenwash bottle, fill it up and see if its leaking from where the pump is fitted you can get another bottle from a good scrappy for about £5-00.
hope it helps
July 2010