There seems to be several important milestones when starting with Microstock Photography:
It shows the telecommunication tower at Ulm, Eselsberg, Baden-Wuerttemberg, Germany at sunset. I took this photo out of the open window of the office building where I am working. As general rule: The light at sun-set or sun-rise is very good. It is often the best time to take photos. Because this photo is an "against-the-light-shot", exposure can be a bit tricky. Exposure analysis via the histogram function of an SLR is important. The camera's automatic exposure control will not function properly in such a situation. Exposure correction is needed. I took around 20 photos and I selected just one for upload at DS. I deleted the rest.
Some other important lessons I learnt:
I wait until a photo is accepted at DS, before I start downloading the raw format as additional format.
When uploading a photo, I provide sufficient but otherwise only quite basic key-wording. I polish my key-wording after the photo is accepted.
With an approval rate of still less than 50% (I hope, this will become better in the near future), I can avoid a lot of work with this approach.