The easiest way to do it is through our policy designer. We only need to select the evidence we want to use and drag it where we would like to place it.
The positions are reflected with the parameters X and Y, taking as reference the lower left part of the document, where the point located in the lower left corner X = 0 Y = 0, with X moving to the right and Y moving up
To make it as easy as possible, this link offers a step-by-step handbook on how to position the evidence and signature stamps from policy designer and via API: