Work your way around the base until the whole squad is superglued down with water-PVA glue around all their boots.
Double check that your water-glue is applied all the way to the rim of the base, you can add more, or brush it outwards a bit to make it all fit. Once you're ready, slowly sprinkle on flocking! Over-do it, just cover them heavily in flocking.
Let them dry overnight, then hold them upside down and tap their bottoms so all the loose un-glued flocking falls off. And whamo! You're done! Repeat as many times as you can stand and you've got an army ready!