You can use color to communicate star temperatures in a cluster by colorizing the shortest wavelength filter blue, colorizing the middle wavelength filter green, and colorizing the longest wavelength filter red, then combining the images.
The next step in creating a full color image is to color balance the image. Color balancing means adjusting the color intensity sliders for each filter until you have an image that effectively conveys astronomical information.
Color balancing does not mean setting the same intensity for each filter.
For instance, if you want to show the blue stars, you may want to increase the intensity of the filter that passes blue light (to which we assigned the color blue).
There are a few general guidelines to follow with color balancing:
Create a color balanced image of this cluster with the hot star appearing blue, and the cool star appearing red. (Data from HSC-SSP and CLAUDS Surveys)