Most fry cutters come with several attachments in different sizes, for example 9x9 mm for thin fries, 10x10 mm for a classic size, or 12x12 mm for thick Belgian-style chips. Each attachment consists of two parts: a back plate and a cutting blade. Make sure you insert the blade with the sharp edge facing inward, otherwise it won't cut properly. Choose the size based on what you want to make and how crispy you want the final result to be. Thinner fries cook faster and become crispier, while thicker fries have a softer interior.

Wash your potatoes thoroughly and peel them if you prefer. For fries with skin you can leave them unpeeled as long as they're clean. Trim the potatoes so they fit the opening of the fry cutter. A potato that's too large won't pass through properly and will give uneven results. Preferably use waxy or slightly floury potatoes — they give the best texture after frying or baking. Potatoes that are too watery will result in limp fries.

A fry cutter isn't just for potatoes. Sweet potato, zucchini or carrot also work well, as long as they fit in the appliance and aren't too hard. Very hard vegetables like raw beetroot or celeriac require more force and can be more difficult. In that case cut them into smaller pieces before pushing them through. Vegetable sticks are a fun and healthier alternative and also look great on the table alongside a dip.

After use, rinse the parts of the fry cutter under warm water. Remove the attachment and the cutting blade separately and be careful when cleaning the blade, as the cutting edge is sharp. Use a dish brush instead of a sponge to protect your fingers. Let the parts dry thoroughly before storing them to prevent rust on the blade. This will keep your fry cutter in good condition and ready for the next batch of homemade fries.