FWIW, I don't recommend stirring the sandbed up ever...there are compounds in the anoxic layers of even a shallow substrate that you do NOT want in your water column. I've had folks wonder why their tanks crashed, and it has often been caused by disturbing the sandbed in this manner. You can gently push your fingers into it to keep it loose, but do not turn it over.
Sandsifters will work until they deplete the sandbed of its valuable microfauna (they're eating when they sift), after which if they don't eat prepared foods (many won't), they'll starve.
Your best bet is to gently siphon the surface of the substrate to remove detritus. As mentioned, Nassarius snails, small conchs, etc. do a nice job of popping in and out of the substrate. If you want a critter to clean your sandbed, get a Holothuria sp. cuke...they take in dirty sand in one end and poop clean sand out the other end, but you're still dealing with losing your sandbed's microfauna.
HTH