Why is my text blurred?

Blurred lettering is caused by one of the following:

i. Your artwork was not clear
Look at it against the light to see if the black edges to the characters are clean.  If it is printed badly then you should change your printer settings (try 'photo paper matte' to give more ink, or increase the ink density, or clean your printer heads or use manufacturer's own brand ink.

ii. Your images are not vectored
By this we mean that you have a bitmapped image that cannot be expanded beyond the size it was created at, so as you expand it you get a saw-toothed edge to the drawings.  The solution is to reduce the size of the image or to use a different format of file.
You exposed your image for longer than you should - the second exposure is not particularly time critical, but if you leave it for another 5 minutes and you have poor quality artwork, you will fill in the detail.

iii. You let light get to the stamp before washing it out
You would have to leave it lying around for a few minutes for this to happen!
You didn’t wash it out properly - use the brush provided, washing up liquid and warm/hot water.  Brush it in a circular motion until it lathers up and is obviously clean.