You can copyright the designs but your idea is not patentable because it doesn't qualify for a patent.

Would you be buying the eye masks and then decoratig them? How much would these cost? Can you get them wholesale?

Have you done any market research to see if anyone would be interested in purchasing these masks?

I think that you first need to figure out if people would want your item, then figure out your budget, basically - fill out a business plan. You probably don't need to actually fill it out, but look at the questions and those will guide you on how to start :-)

Good luck!
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