Methods and apparatuses for assembling a structure onto a substrate. A method according to one aspect of the invention includes dispensing a slurry onto a substrate wherein the slurry includes a first plurality of elements, each of which is designed to mate with a receptor region on said substrate and each of which comprises a functional element, and wherein the slurry also includes a second plurality of elements which are not designed to mate with receptor regions on the substrate. Typically, these second plurality of elements help movement of the first plurality of elements.