Synonyms for Dream up:

n.

fix, plan, finalize, organize, arrange, map out, draw up, think ahead, orchestrate. devise (noun)
imagine, contrive, invent.
dream up (noun)
hatch, think of, think up, concoct.

v.

concoct plan (verb)
hatch, invent, imagine, contrive, think up.
creation (verb)
hatch, think of, think up, concoct.

Other synonyms:

invent, map out, think ahead, finalize. orchestrate. draw up, organize. contrive, arrange, plan. fix. cause
think up.
Other relevant words:
imagine, plan, contrive, organize, arrange, invent.