If you want to destroy your will you should burn it, tear it up or otherwise destroy. Once you have destroyed it in one of these manners the will is revoked providing that you clearly intended to destroy the will.

Is a will that has been accidentally destroyed still valid?

In order to revoke a will by destroying it the person whose will it is must have intended to destroy the will. Where a person accidentally destroys their will the will, therefore, remains valid. From a practical point of view it would, however, be sensible to prepare a new will in such circumstances.

Do copies of the will also need to be destroyed?

Only an original will is a valid will. However, if copies remain, it may be thought that the destruction of the will was accidental. For this reason it is sensible to destroy any copies of the will at the same time. If copies of the will cannot be found to avoid any future confusion it would be sensible to prepare a new will as a new will will supersede the earlier one.

Can I ask someone to destroy my will for me?