I used to be able to change the signature color in Preview. This is no more applicable. And the camera signature yeilds black and white signature. Is there anyways to either color the signature after having it in the Preview of import colored one?
You can get a colored signature by going to Preview and at the appropriate place insert your signature. Now select your signature and click on the box shown in red in the image below. It's the third box from the right.
When you click on this box outlined in red you get the color palette shown in 2nd figure shown below.
You can select the color you desire.