1. Often the opportunity just presents itself - never underestimate serendipity (however its spelled - fancy word for "dumb luck") - or the sort of predictable "long shadows" of evening (anywhere).
2. It helps to kind of "train" your entourage (I.e., husband, son) to exercise their creative vision. In this case, I think it was my son who spotted the photo op, I just took the picture. The only "training" required was to verbally reward him for a couple of good suggestions, and he became my photo scout for the entire trip.
3. You don't need a great digitial - but if you have "iso" setting, you can take this picture with multiple settings, capturing different "lightings" for the same composition - later deleting your least favorites. That is not what I tend to do, as I am still trying to break film "habits" (where experiments cost money) - but certainly anyone with a digital can take this same picture. If your camera has "iso" - read the one page in the manual where it describes use - it will pay off handsomely.
4. You need to feel comfortable looking a little silly - and asking your family to sometimes wait to get the shot. Patience - while you check your composition and lighting (and maybe a technical setting or two). When dealing with people, I find myself saying "I know it feels awkward right now, but 10 years from now, you'll be SO glad I did this!" (They always are - glad that is). I think all 3 pictures, including the towel/napkin backdrop shot, took about 2 minutes.
5. My suggestion to anyone - and my personal practice - to delete ugly pictures unless they have great sentimental value. I don't delete many pictures, but the borderline ones are never posted here.