The key to DAM
is having in place a system that works for you allowing you to search your archives. Usually that is a keyword system. The major image editing systems – Bridge, Aperture, Lightroom, and Photo Mechanic – all allow use of keyword systems.
Also there are a number of keyword development programs or plugins available online to help you develop your keywords. Just Google something like “photo keywords” and see what is currently out there. I found a good list years ago and simply copied it (it would be a lie if I said I always used it on every shoot!).
BTW to conceptualize your DAM workflow, an excellent book to read is The DAM Book by Peter Krogh.