There are two basic ways. Most LLCs are member-managed. This mean that all the members jointly run the business.
Some LLCs are manager-managed. This means that they designate one or more members to be managers or perhaps they hire one or more outside managers. It is possible, as well, to have an LLC that is managed by a combination of members and outside managers.
If you get too complicated about the management arrangements, you may compromise one of the main benefits of using the LLC as your business format: keeping things simple.