had an idea to make my necrons walking into water at a beach as a base but im not skilled enough to know how to pull it off yet

i have AK atlantic blue gel, transparent vallejo gel, vallejo still water, water effect gel and sandy desert texture paste

what is the way to go about doing this? an absurd amount of days doing tiny layers at a time? just do some sand on the one side in a crescent and the blue gel on the other side? get 2 part resin to pour?