there are two ways this can be done.
one is with DCDs (Deep Cheque Documents), as seen on this site.
this is might be suitable if you are interested or have experience in selling Art - contact me and i will explain.
the other way (known as DCIS) is with DCNotes, which is a quite different concept.
that option is much wider, suitable for just about any project, business or activity.
there are certain requirements but they are easier to meet, the main one is a genuine interest in feeding creativity.
DCIS is managed by a separate web site, go there for more info: