Using a potentiometer (other than a trim pot) with a 0.1 inch grid bread board can be difficult or inconvenient since in many cases the connecting lugs on the potentiometer usually do not match the 0.1 inch spacing on the bread board.
I have found one solution. The CTS 296 series single turn rotary potentiometers are reasonably priced, small in size and can be easily adapted to use on a bread board. These carbon composition potentiometers are 12mm in size and have a power rating of 0.15 watts.
They are available in 11 different resistance values from 500 ohms to 1meg ohm. The most commonly available have a linear output and a tolerance rating of +/- 20% . The vertical mount type are the ones I used. Matching knobs are also available for use with the knurled plastic shaft.
In order to adapt them to bread board use, I used four pins obtained from a 0.1 inch breakaway header. The pins were then soldered to the pins on the potentiometer. The potentiometer can now be easily plugged into the breadboard.
They seem to work quite well without further modification.
However, for additional support, a loop of 22 awg uninsulated wire can be soldered to the metal tab that is opposite the solder lugs. This loop of wire can then be cut to the correct length and inserted into the bread board along with the header pins.