Simply dial in the colour bands from the resistor using the large colour wheels. As each wheel is set the image of the resistor changes to reflect the chosen colour. Once all of the bands have been set and the displayed image matches your target resistor then the resistance value can be read from the screen. If your resistor has 5 colour bands instead of four then set the slider to show "5 Bands" to update the display to support the additional colour band.
The display will also tell you which of the standard ranges includes the resistance value you have de-coded
Set the required resistance value digits, multiplier and tolerance and the resistor image will show you just what your target resistor should look like. If you enter a value that is not one found in one of the standard ranges then you can use the calculator option to calculate how to achieve your required value by pairing up standard resistances.
Swipe or tap the little widget at the right hand side of the screen. This will display the calculator. The calculator will suggest ways of combining resistors to achieve a value you have already entered on the main screen. You can however change the value to be calculated as well as specify the range from which resistors should be picked to achieve your target resistance. Calculated values are listed in an order that reflects just how close to your target a particular combination should be (subject to the tolerance of the individual resistors you elect to use). You can scroll through the list to find a combination that meets your requirements.
Close the calculator by clicking the close button or swiping towards the edge of the screen.