i think it depends. If you want it a certain way, than you should spell it out for them. If you're okay with them taking your inspiration and running with it, then you can just give a few general ideas.
I didn't use disney for floral but i just told my florist i wanted a mix of flowers in shades of purple and ivory and white and showed him a few inspiration pics of what i was thinking and he completely blew me away with what he came up with. It was so much more beautiful than any of the pictures or anything i could have imagined. They way i thought of it, i just wanted it to be beautiful, i didn't care what type of flowers he used or anything like that. He's the professional so i figured he would know best which flowers to use.
Some brides are very into every little detail, others not so much. I don't think there is a right or wrong way. The very detail oriented brides would be disappointed if things aren't the way they imagine, so the more direction they can give the better. For other brides it might be stressful to dig through tons of pictures and put together slide shows, you just need to do what's right for you

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