Set the Gain of an Opamp Accurately Using a Potentiometer
Limit the range of the pot to the minimum acceptable (but take tolerances into account. Use precision resistors for the external resistances. 
If you use the pot as a potentiometer with series resistors on one or both sides, consider shunting the element with a precision resistor. Pot elements have very poor tolerance and a lot of temperature drift. 
Use a value of pot where the CRV of the wiper will not greatly affect the gain.  Temperature drift specification is not typically something you can hang your hat on. They guarantee the element resistance change with temperature, but generally not the variation of the resistance from end to wiper.
Use a pot with a long circular or helical element if precision is important. Linear elements are more prone to relative CTE of the materials. The number of turns is not a good indication of the stability, only the easy of setting for a sloppy technician.


The optimum circuit really depends on the range of adjustment and the accuracy required. Don't forget you can use analog switches to select different ranges as well, and adjust within the range.