Cutting Old Plates....Please and thank you!!!

A friend knows I have a basementful (well, not quite) of old dishes that I picked up at auctions, garage sales, etc. saving for kids' first apartment or house. She asked if I would be willing to cut some up for materials/supplies for a disabled adult mosaic glass she wants to teach. The adult home has a very nice garden and she wants to create stepping stones for each gardener.

Not a problem but....I am clueless where I sit how to go about this. Do I just pick up a plate, cup, or saucer and smash it on the ground??? Do I need tile cutters or (s)nippers??? She tells me she doesn't need anything fancy but if I can cut details for her rather than just giving her shards, I'd prefer to do that.

Thanks for any help. 'Tis appreciated!!! :)

KM