To fuse dry pastel I use the fuzzes, fingers or soft paper type “Tissue”. Always apply the darker shades first and then go on with the clearer colors. This is contrary to when using oil, where I apply the lighter ones first before adding the dark ones.
To ensure that pastel designs and paintings remain in good condition over time, it is important to use acid-free paper with neutral pH, otherwise they will turn yellow over time. In my paintings I usually use specific paper as it is the most suitable material for the pastel I use.