At Bynder we like to help you the best way we can and we like to make things easier for you. Please send an email to [email protected] and send us the file that you would like to use as a watermark. We will happily set it up for you. Our advice is to make use of a 'png' or 'eps' file with a transparent layer, so that the watermark can nicely overlap the original asset without a background color.
The difference is shown in the image below.