I think you mean "Don't step on the hedgehog." "Don't walk on the hedgehog." is grammatically correct, but
FWIW, the Swedish word for step is trampa, and is the same for the imperative form.
Vem vill faktiskt åka på en igelkott?
I thought 'don't tread on the hedgehog' was more idiomatic in English.
Arnauti, what do you say when you need "to go?"