All will have tools that let you sharpen the focus, lighten or darken the contrast, balance the color, crop or resize the picture, etc. Play around and get to know them. If you have altered and re-altered a picture several times, you have probably lost enough quality that you should scan it again. You will find that certain combinations work best. That's just a rule of thumb, though.
Every picture has to be treated separately.
Otherwise prints do well. So do beads scanned directly. No, they are not going to be the quality that Robert Liu gets for Ornament , but sometimes quality had to be sacrificed for speed, immediacy and the low cost of publishing. Once you have the scan, crop it to leave only a small margin. Names should be no more than 8 characters long.