Start with an even, high-contrast source
Use a signature you are authorized to reproduce. Scan plain paper or photograph it with the camera parallel to the page, in even light without a phone shadow. Leave a small margin around every stroke. Crop away unrelated text before uploading so it does not become another part of the cutout.
This is a network-based removal service, not an offline scanner. A signature image is sensitive: someone with a copy may be able to reuse it. If you do not want to transmit it, use an offline image editor instead. For logos, use the separate logo guide; preserving brand artwork has different checks from preserving handwriting.
Remove the background and inspect thin strokes
A faint pen stroke and a paper shadow may have similar tones. Automatic removal can drop the stroke or keep the shadow. Compare the first and last strokes, dots, crossbars, and enclosed loops with the source. A readable signature at thumbnail size can still have a broken line when placed on a document.
Zoom in and follow the strokes. Erase can clear retained paper, and Restore area can recover visible source pixels, but Restore also brings back paper within the brush. If a narrow stroke needs repeated repairs, rescan with better contrast or use a level or threshold adjustment in an offline editor. A threshold can suit solid dark ink, but can erase faint ink and harden smooth edges.
Export a transparent file
Choose the Transparent background and the PNG format. JPG has no transparency and is saved on white, which defeats the purpose of a signature you want to place over a document.
Original size keeps the working canvas, including empty space around the signature. A Landscape preset creates a fixed 1920 by 1080 canvas; it is not a tight crop and can enlarge a small scan. For a compact signature asset, crop the transparent PNG around the strokes in your document or image editor without resizing it unnecessarily.
Test the signature at its document size
As an example, a signature cropped to 900 pixels wide and placed 3 inches wide provides 300 pixels per inch. That calculation describes the available raster detail, not legal validity or a guaranteed print standard. Keeping a full-page scan around a tiny signature can make placement awkward even when the file itself has many pixels.
Place the PNG over a pale-colored document area, check that the paper rectangle is gone, and compare the writing with the original. Export the finished document to PDF and inspect it again. Confirm that the document has not stretched the signature, clipped a flourish, or reduced faint lines until they disappear.
Use signatures responsibly
A pasted signature image does not by itself verify who signed, record consent, or provide an audit trail. Whether it is acceptable depends on the document, recipient, and applicable law. Follow the recipient's signing process; when identity verification or an audit trail is required, use the specified signing service rather than treating a PNG as an equivalent.