Don't bother! My seven year old daughter spent hours, painstakingly pinning sequins into place, and we ran out of sequins long before reaching the end of the project.
I have to say that up to this point she was loving it! As a concept it is brilliant for the 7-9 age group: fast and impressive (sparkly) results, easy for the child to do alone but the whole family could get involved. We were loving it...
But to run out of sequins before the project is completed, having put so much effort in, is devastating for a child.
So I really wouldn't bother!