No matter how large large I sign a piece of paper or how large a graphic file I use, or the format I save it as (PNG, PDF, JPG), when I go to actually place my signature in a signature box, the resulting image is tiny, as well as not terribly bold. One, how do I increase the size of how my scanned signature appears? And two, how do I make it appear more bold? Thank you for your help.
Rescan it at higher resolution after resigning it with a heavier pen.
There are electronic ways to bolden the old one but it may end up looking false. Sign fairly large and scan at 600dpi, save as .psd and .jpg for various purposes or methods of creating your PDF and choose the one that works best. If you are using Word or similar app, then maybe try a .png also.
As it turns out, the way to make the image appear larger on the page is to edit and increase the size of the signature "box" on the pdf (under Forms > Add or Edit Fields), to considerably larger than the form might indicate. Otherwise, the signature is constrained to the just the size of the small field on the pdf. Interestingly, as soon as you do so, the signature appears "bolder", likely just because there is more of it. Thanks for your suggestions!