There are two types of lasting powers of attorney (LPA): health and welfare; and property and financial affairs. If a person is capable of dealing with their own affairs at present they can make either or both types of LPA.
A finance LPA can be used as soon as the Office of the Public Guardian has registered it. But, a health and welfare LPA can only be used when the person can no longer look after their own affairs. A lasting power of attorney gives another person authority to act on your behalf.