Power to fixture to switch - How to wire?
The current Code requires that neutral even if you don't use it

You will need to use 14/3 for the run from the fixture to the switch (called a switch loop in the trade).  This is governed by NEC 404.2(C):


  (C) Switches Controlling Lighting Loads. The grounded
  circuit conductor for the controlled lighting circuit shall be
  installed at the location where switches control lighting loads
  that are supplied by a grounded general-purpose branch circuit
  serving bathrooms, hallways, stairways, or rooms suitable for
  human habitation or occupancy as defined in the applicable
  building code. Where multiple switch locations control the
  same lighting load such that the entire floor area of the room
  or space is visible from the single or combined switch locations,
  the grounded circuit conductor shall only be required at one
  location. A grounded conductor shall not be required to be
  installed at lighting switch locations under any of the following
  conditions:
  
  (1) Where conductors enter the box enclosing the switch
  through a raceway, provided that the raceway is large
  enough for all contained conductors, including a grounded conductor
  
  (2) Where the box enclosing the switch is accessible for the
  installation of an additional or replacement cable without
  removing finish materials
  
  (3) Where snap switches with integral enclosures comply with
  300.15(E)
  
  (4) Where lighting in the area is controlled by automatic
  means
  
  (5) Where a switch controls a receptacle load
  
  The grounded conductor shall be extended to any switch
  location as necessary and shall be connected to switching devices that require line-to-neutral voltage to operate the electronics of the switch in the standby mode and shall meet the requirements of 404.22.
  
  Exception: The connection requirement shall become effective on January 1, 2020. It shall not apply to replacement or retrofit switches installed in locations prior to local adoption of 404.2(C) and where the
  grounded conductor cannot be extended without removing finish materials. The number of electronic lighting control switches on a branch
  circuit shall not exceed five, and the number connected to any feeder on
  the load side of a system or main bonding jumper shall not exceed 25.
  For the purpose of this exception, a neutral busbar, in compliance with
  200.2(B) and to which a main or system bonding jumper is connected
  shall not be limited as to the number of electronic lighting control
  switches connected.
  
  Informational Note: The provision for a (future) grounded
  conductor is to complete a circuit path for electronic lighting
  control devices.


(Note that in an unfinished basement, point 2 of the above may hold, but I would still run the 14/3 cable anyway -- it's cheaper to do it right now than to fix it later.)