If you want to get rid of the white box around it you'll need to do the whole process again, and be sure to include step 4, or.....it's just fine the way it is!
Click: "Click here to start"
You can either register (they will save your signature) or just proceed.
Click: "Use the signature creation wizard"
step 1: fill in your name (click "next step")
step 2: select the font you want to use (click "next step")
step 3: select the size you want to use (click "next step")
step 4: select the color you want to use (click "next step")
Click on "transparent" to avoid a white box around your name and click around in the large square until
the color you want shows up in the second rectangle.
step 5: select the slope you want to use (click "next step")
