Today I had a question from an artist about how I sign my work. Here's my reply for all to see:
"Signing work is a frustration, isn't it. Yes, I do use paint diluted with thinner and a liner brush. Often, it takes two or three attempts to get an acceptable signature. If the paint is wet, I usually try to keep the background in that area pretty simple in case I have to blend out a aborted signature. I'd rather not be forced to conserve color interest or brushwork beneath it.
Sometimes, it's easier to do after the paint is dry. However, if it is applied after the painting is varnished, it becomes a 'floating' signature, about which conservators should be forewarned.
I have considered taking a scanned copy of one of my better signatures to Office Depot to have a rubber stamp made, perhaps in three sizes, but haven't yet. Other artists do this from time to time, including Nicholi Fechin, so I don't think it is a questionable practice. A problem arises, though, when someone uses the stamp after the artist's death, as I believe they did in Fechin's case, to sign incomplete or substandard work that the artist felt was not good enough or complete enough to sign.
In the end, I think the best thing to do is to practice your signature often, training your muscle memory so that you can do it with both ease and confidence. Doing so helps me, though I don't practice as often as I should."