So I have a 2012 convertible V6 Ford Mustang and there is a very small crack developing in a crease on my roof:
I believe the top is made from Vinyl and I must confess that I've neglected it. The first 2 years of the cars life were outdoors and I tried to clean off crud with water when it got on there, the last 2 1/2 years have been garaged and the car has only been out in good weather.
How can I mend this tear, and what kind of stuff do I need to treat the top with to prevent this from happening again? I'd like for this baby to last!
Here is a slightly larger view of the roof - I'm pointing at the location of the crack:

